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1

The origin and distribution of the E1 strength over low-lying states in well-deformed nuclei  

SciTech Connect

The energies and wave functions of the K{sup {pi}} = 0{sup {minus}} and 1{sup {minus}} states in {sup 158}Gd, {sup 162,164}Dy, and {sup 168}Er are calculated in the RPA, taking the isoscalar and isovector particle-hole and particle-particle octupole and isovector particle-hole dipole interactions into account. It is shown that the inclusion of the isovector dipole interaction in addition to the octupole interactions leads to the shift of the largest part of the E1 strength from low-lying states to the GDR. The origin of the E1 strength in the low-energy region is explained as an effect of the quadrupole equilibrium deformation and isoscalar octupole and isovector dipole interactions. At excitation energies below 4 MeV, the total E1 strength for K{sup {pi}} = 0 states is 3 to 4 times as large as that for the K{sup {pi}} = 1{sup {minus}} states. The fragmentation of the one-phonon K{sup {pi}} = 0{sup {minus}} and 1{sup {minus}} states in {sup 164}Dy and {sup 168}Er due to coupling with the two-phonon configuration is calculated. The B(E1) values for the first K{sub v}{sup {pi}} = 0{sub 1}{sup {minus}} states are 3-5 times as large as the experimental values. The concentration of the E1 strength over the K{sup {pi}} = 0{sup {minus}} states at energies 2.6-3.5 MeV in {sup 168}Er and 3.6-3.9 MeV in {sup 164}Dy is predicted. 45 refs., 2 figs., 4 tabs.

Soloviev, V.G.; Sushkov, A.V. [Joint Institute for Nuclear Research, Dubna (Russian Federation)

1994-08-01

2

Relativistic two-phonon model for the low-energy nuclear response  

NASA Astrophysics Data System (ADS)

A two-phonon version of the relativistic quasiparticle time-blocking approximation introduces a new class of many-body models for nuclear structure calculations based on the covariant energy density functional. As a fully consistent extension of the relativistic quasiparticle random phase approximation, the relativistic two-phonon model implies fragmentation of nuclear states over two-quasiparticle and two-phonon configurations coupled to each other. In particular, we show how the lowest two-phonon 1- state, identified as a member of the [2+?3-] quintuplet, emerges from the coherent two-quasiparticle pygmy dipole mode in vibrational nuclei. The inclusion of the two-phonon configurations into the model space allows a quantitative description of the positions and the reduced transition probabilities of the lowest 1- states in tin isotopes 112,116,120,124Sn as well as the low-energy fraction of the dipole strength below the giant dipole resonance without any adjustment procedures. The model is applied to the low-lying dipole strength in neutron-rich 68,70,72Ni isotopes. Recent experimental data for 68Ni are reproduced fairly well.

Litvinova, Elena; Ring, Peter; Tselyaev, Victor

2013-10-01

3

Evolution of the Low-lying E1 Strength With Deformation  

SciTech Connect

The evolution of low-lying E1 strength is systematically analyzed in very neutron-rich Sn nuclei, beyond {sup 132}Sn until {sup 166}Sn, within the Relativistic Quasiparticle Random Phase Approximation. The great neutron excess favors the appearance of a deformed ground state for {sup 142-162}Sn. The evolution of the low-lying strength in deformed nuclei is determined by the interplay of two factors, isospin asymmetry and deformation: while greater neutron excess increases the total low-lying strength, deformation hinders and spreads it. Very neutron rich deformed nuclei may not be as good candidates as spherical nuclei like {sup 132}Sn for the experimental study of low-lying E1 strength.

Arteaga, D. Pena; Khan, E. [Institut de Physique Nucleaire, Universite Paris-Sud, IN2P3-CNRS, F-91406 Orsay Cedex (France); Ring, P. [Physikdepartment, Technische Universitaet Muenchen, D-85748, Garching (Germany)

2009-08-26

4

Measurement of the E1 strength function of {sup 11}Be  

SciTech Connect

The authors have investigated the E1 strength function of {sup 11}Be by Coulomb excitation and measurement of the subsequent projectile photon decay. The photons were measured in a wall of BaF{sub 2} detectors. The authors have used the virtual photon method to extract the photoabsorption cross section and hence the dipole strength function. They compare the findings with sum rule predictions. This is a first example of techniques they will extend to heavier mass nuclei.

Varner, R.L.; Gan, N.; Beene, J.R. [Oak Ridge National Lab., TN (United States). Physics Div.]|[Michigan State Univ., East Lansing, MI (United States)

1998-11-01

5

Measurement of the E1 strength function of {sup 11}Be  

SciTech Connect

We have investigated the E1 strength function of {sup 11}Be by Coulomb excitation and measurement of the subsequent projectile photon decay. The photons were measured in a wall of BaF{sub 2} detectors. We have used the virtual photon method to extract the photabsorption cross section and hence the dipole strength function. We compare our findings with sum rule predictions. This is a first example of techniques we will extend to heavier mass nuclei.

Varner, R. L.; Gan, N.; Beene, J. R.; Halbert, M. L.; Stracener, D. W.; Azhari, A.; Ramakrishnan, E.; Thirolf, P.; Thoennessen, M. R.; Yokoyama, S. [Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee (United States); Department of Physics and Astronomy and National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan (United States)

1998-12-21

6

Measurement of the E1 strength function of {sup 11}Be  

SciTech Connect

We have investigated the E1 strength function of {sup 11}Be by Coulomb excitation and measurement of the subsequent projectile photon decay. The photons were measured in a wall of BaF{sub 2} detectors. We have used the virtual photon method to extract the photabsorption cross section and hence the dipole strength function. We compare our findings with sum rule predictions. This is a first example of techniques we will extend to heavier mass nuclei. {copyright} {ital 1998 American Institute of Physics.}

Varner, R.L.; Gan, N.; Beene, J.R.; Halbert, M.L.; Stracener, D.W.; Azhari, A.; Ramakrishnan, E.; Thirolf, P.; Thoennessen, M.R.; Yokoyama, S. [Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee (United States)]|[Department of Physics and Astronomy and National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan (United States)

1998-12-01

7

B(E1) Strengths from Coulomb excitation of 11Be  

SciTech Connect

The B(E1;1/2{sup +}{yields} 1/2{sup -}) strength for {sup 11}Be has been extracted from intermediate energy Coulomb excitation measurements, over a range of beam energies using a new reaction model, the extended continuum discretized coupled channels (XCDCC) method. In addition, a measurement of the excitation cross section for {sup 11}Be+{sup 208}Pb at 38.6 MeV/nucleon is reported. The B(E1) strength of 0.105(12) e{sup 2}fm{sup 2} derived from this measurement is consistent with those made previously at 60 and 64 MeV/nucleon, in contrast to an anomalously low result obtained at 43 MeV/nucleon. By coupling a multi-configuration description of the projectile structure with realistic reaction theory, the XCDCC model provides for the first time a fully quantum mechanical description of Coulomb excitation. The XCDCC calculations reveal that the excitation process involves significant contributions from nuclear, continuum, and higher-order effects. An analysis of the present and two earlier intermediate energy measurements yields a combined B(E1) strength of 0.105(7) e{sup 2}fm{sup 2}. This value is in good agreement with the value deduced independently from the lifetime of the 1/2{sup -} state in {sup 11}Be, and has a comparable precision.

Summers, N C; Pain, S D; Orr, N A; Catford, W N; Angelique, J C; Ashwood, N I; Bouchat, V; Clarke, N M; Curtis, N; Freer, M; Fulton, B R; Hanappe, F; Labiche, M; Loucey, J L; Lemmon, R C; Mahboub, D; Ninane, A; Normand, G; Nunes, F M; Soic, N; Stuttge, L; Timis, C N; Thompson, I; Winfield, J S; Ziman, V

2007-03-06

8

E1 oscillator strengths and transition rates among levels of Cl I  

NASA Astrophysics Data System (ADS)

We present oscillator strengths and transition rates of E1 transitions between the fine-structure levels belonging to the configurations 3s23p5, 3s3p6, and 3s23p4nl, where nl= 4s, 5s, 6s, 4p, 5p, 3d, 4d. The calculations have used extensive configuration interaction (CI) wavefunctions, with the associated Hamiltonian matrix adjusted to ensure that the eigenenergies agree with experimental energy level data ('fine tuning'). There are consequential small changes in the CI mixing coefficients from their ab initio values and these corrected coefficients are used in the calculation of the transition data. The method of optimization of the orbital radial functions (expressed in terms of Slater-type orbitals) is described and the radial function parameters are also presented. We show some comparisons between our work and those of earlier calculations and demonstrate how the inclusion of relativistic effects (which we achieve through the use of the Breit-Pauli approximation) can result in a substantial redistribution of the oscillator strength from the LS calculation. We also demonstrate that the fine-tuning process can make, particularly for intercombination lines, a substantial improvement in the agreement between theoretical and experimental oscillator strengths.

Oliver, P.; Hibbert, A.

2013-07-01

9

Discovery of low-lying E1 and M1 strengths in {sup 232}Th  

SciTech Connect

Properties of low-energy dipole states in {sup 232}Th have been investigated with the nuclear resonance fluorescence technique. The present work used monoenergetic {gamma}-ray beams at energies of 2-4 MeV from the high-intensity {gamma}-ray source at Triangle Universities Nuclear Laboratory. Over 40 transitions corresponding to deexcitation to the ground state and first excited state were observed for the first time. Excitation energies, integrated cross sections, decay widths, branching ratios, and transition strengths for those states in {sup 232}Th were determined and compared with quasiparticle random-phase-approximation calculations. A large number of E1 transitions were observed for the first time in actinide nuclei with summed strength of 3.28(69)x10{sup -3} e{sup 2} fm{sup 2}. The observed summed M1 strength of 4.26(63){mu}{sub N}{sup 2} is in good agreement with the other actinides and with the systematics of the scissors mode in deformed rare-earth nuclei.

Adekola, A. S.; Hammond, S. L.; Hill, A.; Karwowski, H. J. [Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708 (United States); Angell, C. T. [Department of Nuclear Engineering, University of California, Berkeley, California 94720 (United States); Howell, C. R.; Kwan, E. [Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708 (United States); Department of Physics, Duke University, Durham, North Carolina 27708 (United States); Kelley, J. H. [Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708 (United States); Department of Physics, North Carolina State University, Raleigh, North Carolina 27695 (United States)

2011-03-15

10

Transition probabilities and oscillator strengths of E1 transitions in Fe XII and Fe XIV  

SciTech Connect

Non-orthogonal orbitals in the multiconfiguration Hartree-Fock approach are used to calculate line strengths, oscillator strengths and transition probabilities for E1 transitions among the fine-structure levels of the 3s{sup 2}3p{sup 3}, 3s3p{sup 4}, 3s{sup 2}3p{sup 2}3d, 3s3p{sup 3}3d, 3p{sup 5} and 3s{sup 2}3p3d{sup 2} configurations in Fe XII and 3s{sup 2}3p, 3s3p{sup 2}, 3s{sup 2}3d, 3p{sup 3}, 3s3p3d, 3p{sup 2}3d, 3s3d{sup 2}, 3p3d{sup 2}, 3s{sup 2}4s, 3s{sup 2}4p, 3s3p4s and 3s{sup 2}4d configurations in Fe XIV. The lifetimes of excited levels belonging to these configurations of Fe XII and Fe XIV are also presented. An accurate representation of the levels has been obtained using spectroscopic and correlation radial functions. The wavefunctions exhibit large correlations and significant dependence of one-electron valence orbitals due to both the total and intermediate terms. The relativistic corrections are included through the one-body and two-body operators in the Breit-Pauli Hamiltonian. Progressively larger calculations are performed to check for important electron correlation contributions and for convergence of results. The atomic wavefunctions give excitation energies which are in close agreement with experiment. The present oscillator strengths and transition probabilities compare very well with previous large scale calculations. - Highlights: {yields} Fe XII and Fe XIV oscillator strengths and transition probabilities for E1 transitions. {yields} Energies and lifetimes of excited levels of Fe XII and Fe XIV. {yields} Multiconfiguration Hartree-Fock calculations with non-orthogonal radial functions.

Tayal, S.S., E-mail: stayal@cau.edu

2011-09-15

11

Two-phonon octupole excitation in {sup 146}Gd  

SciTech Connect

Based on experimental evidence from the {sup 144}Sm({alpha},2n) reaction, the 3484.7-keV 6{sup +} state in {sup 146}Gd is identified as the highest-spin member of the 3{sup -} x 3{sup -} two-phonon octupole quartet. A previously unknown {gamma} line of 1905.8 keV and E3 character feeding the 3{sup -} octupole state has been observed. These results represent the first observation of a 6{sup +}->3{sup -}->0{sup +} cascade of two E3 transitions in an even-even nucleus and provide strong support for the interpretation of the 6{sup +} state as a two-phonon octupole excitation.

Caballero, L.; Rubio, B.; Nacher, E. [Instituto de Fisica Corpuscular, CSIC-Universidad de Valencia, E-46071 Valencia (Spain); Kleinheinz, P. [Institut fuer Kernphysik, Forschungszentrum Juelich, D-52425 Juelich (Germany); Yates, S. W. [Departments of Chemistry and Physics and Astronomy, University of Kentucky, Lexington, Kentucky, 40506-0055 (United States); Algora, A. [Instituto de Fisica Corpuscular, CSIC-Universidad de Valencia, E-46071 Valencia (Spain); Institute of Nuclear Research of the Hungarian Academy of Sciences, Debrecen H-4001 (Hungary); Dewald, A.; Fitzler, A.; Jolie, J.; Linnemann, A.; Moeller, O. [Institut fuer Kernphysik, Universitaet zu Koeln, D-50937 Koeln (Germany); Gadea, A. [Instituto de Fisica Corpuscular, CSIC-Universidad de Valencia, E-46071 Valencia (Spain); Laboratori Nazionali de Legnaro, INFN, I-35020 Legnaro (Italy); Julin, R.; Piiparinen, M. [Department of Physics, University of Jyvaeskylae, FIN-40014 Jyvaeskylae (Finland); Lunardi, S.; Menegazzo, R. [Laboratori Nazionali de Legnaro, INFN, I-35020 Legnaro (Italy); Blomqvist, J. [Research Institute of Physics, S-10405 Stockholm 50 (Sweden)

2010-03-15

12

Relativistic effects in E1 transition oscillator strengths along the Yb+ isoelectronic sequence  

NASA Astrophysics Data System (ADS)

Electric dipole transition oscillator strengths have been computed for low-lying transitions in the Yb+ isoelectronic sequence (through Ra19 +) in fully relativistic and non-relativistic-limit approximations. Relativistic effects were carefully investigated and efforts were undertaken to establish systematic trends in relativistic contributions to oscillator strengths along the Yb+ isoelectronic sequence.

Migdalek, J.; Siegel, W.

2014-04-01

13

Low-lying E1,M1, and E2 strength distributions in {sup 124,126,128,129,130,131,132,134,136}Xe: Systematic photon scattering experiments in the mass region of a nuclear shape or phase transition  

SciTech Connect

Systematic nuclear resonance fluorescence (NRF) experiments on all nine stable (seven even-even and two odd-mass) Xe isotopes have been performed at the bremsstrahlung facility of the 4.3-MV Stuttgart Dynamitron accelerator. For the first time thin-walled, high-pressure gas targets (about 70 bar) with highly enriched target material were used in NRF experiments. Precise excitation energies, transition strengths, spins, and decay branching ratios were obtained for numerous states, most of them previously unknown. The systematics of the observed E1 two-phonon excitations (2{sup +}x3{sup -}) and M1 excitations to 1{sup +} mixed-symmetry states in the even-even isotopes are discussed with respect to the new critical point symmetry E(5). The fragmentation of these fundamental dipole excitation modes in the odd-mass isotopes {sup 129,131}Xe is shown and discussed. In the even-even nuclei several low-lying E2 excitations were observed.

Garrel, H. von; Kneissl, U.; Kohstall, C.; Pitz, H.H.; Scheck, M.; Stedile, F.; Walter, S. [Institut fuer Strahlenphysik, Universitaet Stuttgart, D-70569 Stuttgart (Germany); Brentano, P. von; Fransen, C.; Friessner, G.; Hollmann, N.; Jolie, J.; Linnemann, A.; Muecher, D.; Pietralla, N.; Scholl, C.; Werner, V. [Institut fuer Kernphysik, Universitaet zu Koeln, D-50937 Cologne (Germany); Kaeppeler, F.; Wisshak, K. [Institut fuer Kernphysik, Forschungszentrum Karlsruhe, D-76021 Karlsruhe (Germany); Kaeubler, L. [Institut fuer Kern- und Hadronenphysik, Forschungszentrum Rossendorf, D-01314 Dresden (Germany)] (and others)

2006-05-15

14

Two-Phonon Octupole Excitation in 146Gd  

SciTech Connect

The excited states in 146Gd have been re-investigated with the 144Sm({alpha},2n) reaction using a modern Ge {gamma}-ray array including a polarimeter. Amongst the non-yrast states populated in this reaction we have identified the aligned 6+ member of the two-phonon octupole quartet from the observation of the E3 branching to the one phonon 3- state. Our results represent the first observation of a 6+{yields}3-{yields}0+ E3 cascade in an even-even nucleus.

Caballero, L.; Rubio, B.; Algora, A.; Nacher, E. [Instituto de Fisica Corpuscular, CSIC-Univ. de Valencia, E-46071 Valencia (Spain); Kleinheinz, P. [Institut fuer Kernphysik, Forschungszentrum Juelich, D-52425 Juelich (Germany); Dewald, A.; Fitzler, A.; Jolie, J.; Linnemann, A.; Moeller, O. [Institut fuer Kernphysik, University of Cologne, Cologne (Germany); Gadea, A. [Laboratori Nazionali di Legnaro, INFN, Legnaro (Italy); Julin, R.; Piiparinen, M. [Department of Physics, University of Jyvaeskylae, FIN-40014 Jyvaeskylae (Finland); Lunardi, S.; Menegazzo, R. [Dipartimento di Fisica, Sezione di Padova, Padova (Italy); INFN, Sezione di Padova, Padova (Italy); Yates, S.W. [Department of Chemistry, Univ. of Kentucky, Lexington, KY 40506-0055 (United States); Department of Physics and Astronomy, Univ. of Kentucky, Lexington, KY 40506-0055 (United States)

2005-11-21

15

Two-Phonon Octupole Excitation in 146Gd  

SciTech Connect

The excited states in 146Gd have been re-investigated with the 144Sm({alpha},2n) reaction using a modern Ge {gamma}-ray array including a polarimeter. Amongst the non-yrast states populated in this reaction we have identified the aligned 6+ member of the two-phonon octupole quartet from the observation of the E3 branching to the one phonon 3- state. Our results represent the first observation of a 6+{yields}3-{yields}0+ E3 cascade in an even-even nucleus.

Caballero, L.; Rubio, B.; Nacher, E. [Instituto de Fisica Corpuscular, CSIC-Univ. de Valencia, E-46071 Valencia (Spain); Kleinheinz, P. [Institut fuer Kernphysik, Forschungszentrum Juelich, D-52425 Juelich (Germany); Algora, A. [Instituto de Fisica Corpuscular, CSIC-Univ. de Valencia, E-46071 Valencia (Spain); Institute of Nuclear Research, Debrecen (Hungary); Blomqvist, J. [Department of Physics, Royal Institute of Technology, Stockholm (Sweden); Dewald, A.; Fitzler, A.; Jolie, J.; Linnemann, A.; Moeller, O. [Institut fuer Kernphysik, University of Cologne, Cologne (Germany); Gadea, A. [Laboratori Nazionali di Legnaro, INFN, Legnaro (Italy); Julin, R.; Piiparinen, M. [Department of Physics, University of Jyvaeskylae, FIN-40014 Jyvaeskylae (Finland); Lunardi, S.; Menegazzo, R. [Dipartimento di Fisica, Padova (Italy); INFN, Sezione di Padova, Padova (Italy); Yates, S. W. [Department of Chemistry, Univ. of Kentucky, Lexington, KY 40506-0055 (United States); Department of Physics and Astronomy, Univ. of Kentucky, Lexington, KY 40506-0055 (United States)

2006-04-26

16

New probe of M1 and E1 strengths in GDR regions  

NASA Astrophysics Data System (ADS)

The M1 strengths (or level density of 1+ states) are of importance for estimation of interaction strengths between neutrinos and nuclei for the study of the supernova neutrino-process. In 1957, Agodi predicted theoretically angular distribution of neutrons emitted from states excited via dipole transitions with linearly polarized gamma-ray beam at the polar angle of ?=90° should be followed by a simple function, a + b cos(2?), where ?, is azimuthal angel. However, this theoretical prediction has not been verified over the wide mass region except for light nuclei as deuteron. We have measured neutron angular distributions with (polarized gamma, n) reactions on Au, Nal, and Cu. We have verified the Agodi's prediction for the first time over the wide mass region. This suggests that (polarized gamma, n) reactions may be useful tools to study M1 strengths in giant resonance regions.

Hayakawa, T.; Ogata, K.; Miyamoto, S.; Mochizuki, T.; Horikawa, K.; Amano, S.; Imazaki, K.; Li, D.; Izawa, Y.; Chiba, S.

2014-05-01

17

Direct observation of two-phonon bound states in ZnTe  

NASA Astrophysics Data System (ADS)

A coherent two-phonon bound state has been impulsively generated in ZnTe(110) via second-order Raman scattering in the time domain. The two-phonon bound state, composed of two acoustic phonons anticorrelated in a wave vector, exhibits full ?1 symmetry and has energy higher than the corresponding 2TA(X) overtone. By suppressing two-phonon fluctuations with a double-pulse excitation, the coexistence of coherently excited bound and unbound two-phonon states has been demonstrated.

Hu, Jianbo; Misochko, Oleg V.; Nakamura, Kazutaka G.

2011-12-01

18

Reinvestigation of two-phonon bound states in rare-gas crystals  

Microsoft Academic Search

The existence of two-phonon bound states in rare-gas crystals has been reexamined without resorting to some of the approximations made in the past. The reinvestigation was necessitated due to the failure of the experiments to observe the two-phonon bound states predicted earlier. The present, more-careful calculation gives results for the bound-state energies in close agreement with earlier values. However, the

Rajiv Bhandari; V. K. Jindal; K. N. Pathak

1990-01-01

19

Two-phonon character of the lowest J?=1- state of 142Nd  

NASA Astrophysics Data System (ADS)

The decay properties of the 3424-keV 1- state in 142Nd, which has long been interpreted as a member of the quadrupole-octupole two-phonon quintet, and of the lowest 3- state, the octupole phonon, have been examined with the (n,n'?) reaction. ?-ray branching ratios of these states have been determined, and level lifetimes have been measured by the Doppler-shift attenuation method. These data provide strong support for interpreting the 1- state as having a significant two-phonon 2+?3- component.

Belgya, T.; Gatenby, R. A.; Baum, E. M.; Johnson, E. L.; Diprete, D. P.; Yates, S. W.; Fazekas, B.; Molnár, G.

1995-11-01

20

Search for Two-Phonon Octupole Vibrational States and Multiplets in sr and zr Nuclei  

NASA Astrophysics Data System (ADS)

Excited states in 88Sr were re-analyzed by assigning the new spins and parities according to the published DCO ratios (RDCO). Several new gamma transitions were identified in 92,93,94,96,97Sr and 96,97Zr from the spontaneous fission of 252Cf. Excited states in 88,92,93,94,96Sr and 95,96,97,98Zr were reanalyzed and reorganized to search for the new two-phonon octupole vibrational states and bands. Two-phonon octupole vibrational (POV) states are proposed for the spherical Sr and Zr nuclei near 88Sr and 96Zr. Multiple excited states (multiplets) with the same configuration in 88Sr were interpreted as the weak coupling of a 2+ one-phonon quadrupole or a 3- one-phonon octupole vibration to the excited 8+ state for 88Sr.

Hwang, J. K.; Hamilton, J. H.; Ramayya, A. V.; Brewer, N. T.; Wang, E. H.; Luo, Y. X.; Rasmussen, J. O.; Zhu, S. J.

2014-09-01

21

Two-dimensional image edge enhancement in the two-phonon diffraction  

SciTech Connect

We suggest using the two-phonon Bragg scattering regime for two-dimensional image edge enhancement by means of acousto-optic (AO) diffraction on a single sound wave. Image edge enhancement is demonstrated in the first diffraction order by using an AO cell made of the TeO{sub 2} single crystal. To explain this effect, a three-dimensional model of AO interaction is proposed, which takes into account the angular selectivity of diffraction both in the plane of Bragg scattering and in the plane orthogonal to it. (optical data processing)

Kotov, V M; Averin, S V; Shkerdin, G N; Voronko, A I [V.A.Kotel'nikov Institute of Radio Engineering and Electronics, Russian Academy of Sciences, Fryazino, Moscow Region (Russian Federation)

2010-06-23

22

Cooperative two-phonon absorption in solid ?-nitrogen in the 4600-4700 cm -1 region  

NASA Astrophysics Data System (ADS)

The spectrum of pure ?-nitrogen was recorded with a Fourier transform spectrometer in the near infrared. Two bands at 4657.3 and 4618.7 cm -1, previously studied at low resolution by Grundy et al. (Icarus 105 (1993) 254.), were recorded at 5 K at high resolution and analyzed. The effect of the temperature, impurities and crystal defects was investigated at lower resolution. The first band, due to a simultaneous excitation of two vibrons, exhibits a peculiar shape with several singularities. The vibron energy and the induced dipole moments have been calculated as a function of the crystal wave vector and used in the standard two-phonon theory. By changing somewhat these coefficients from their ab initio calculated values, the shape and the intensity are fairly well reproduced. The second band, narrower and much weaker, is due to the simultaneous excitation of the molecules in the 14N 15N,N 2 couples.

Legay, F.; Legay-Sommaire, N.

1996-06-01

23

Two-phonon 1{sup -} state in {sup 112}Sn observed in resonant photon scattering  

SciTech Connect

Results of a photon scattering experiment on {sup 112}Sn using bremsstrahlung with an endpoint energy of E{sub 0}=3.8 MeV are reported. A J=1 state at E{sub x}=3434(1) keV has been excited. Its decay width into the ground state amounts to {gamma}{sub 0}=151(17) meV, making it a candidate for a [2{sup +}x3{sup -}]1{sup -} two-phonon state. The results for {sup 112}Sn are compared with quasiparticle-phonon model calculations as well as the systematics of the lowest lying 1{sup -} states established in other even-mass tin isotopes. In contrast to findings in the heavier stable even-mass Sn isotopes, no 2{sup +} states between 2 and 3.5 MeV excitation energy have been detected in the present experiment.

Pysmenetska, I.; Enders, J.; Karg, O.; Neumann-Cosel, P. von; Ponomarev, V.Yu.; Volz, S. [Institut fuer Kernphysik, Technische Universitaet Darmstadt, Schlossgartenstrasse 9, D-64289 Darmstadt (Germany); Walter, S.; Garrel, H. von; Kneissl, U.; Kohstall, C.; Pitz, H.H.; Scheck, M.; Stedile, F. [Institut fuer Strahlenphysik, Universitaet Stuttgart, Allmandring 3, D-70569 Stuttgart (Germany)

2006-01-15

24

Spectroscopy of excited states in 234U and search for a two-phonon state in 234U  

NASA Astrophysics Data System (ADS)

Excited states of the isotope 234U were studied employing the one-neutron transfer reaction 235U(d,t)234U at a beam energy of 11 MeV. The reaction channel was selected by an identification of the outgoing tritons in a ?E-E measurement. In coincidence with the tritons, ? rays were also detected with the highly efficient MINIBALL spectrometer. Based on the analysis of ?? coincidence data, the level scheme of 234U was extended. The 4+ state at an energy of 1886.7 keV provides evidence for a possible two-phonon ?? excitation, which is based on three ? transitions from this state to the ? vibrational band. However, this state is populated with a high cross section via the one-neutron transfer reaction, which is not expected for a highly collective excitation. The situation is compared to other known cases from the rare-earth region and to the neighboring isotone 232Th, which so far is the only known case for a two-phonon excitation in the actinide region.

Kotthaus, T.; Reiter, P.; Bruyneel, B.; Chatzistamatiou, M.; Eberth, J.; Gersch, G.; Hess, H.; Stefanescu, I.; Warr, N.; Weisshaar, D.; Wiens, A.; Morgan, T.; Lutter, R.; Schwerdtfeger, W.; Thirolf, P. G.; Bringel, P.; Hübel, H.; Neusser-Neffgen, A.

2013-12-01

25

Direct and two-phonon Orbach-Aminov type spin-lattice relaxation in molecular magnet V15  

NASA Astrophysics Data System (ADS)

In this article we propose a model of spin-phonon relaxation in K6[VIV 15As6O42(H2O)]-8H2O, the so called V15 cluster exhibiting the unique layered magnetic structure. The work is motivated by the recent observation of the Rabi oscillation [1] in this system and aimed to elucidate the role of spin-phonon interaction as a source of decoherence. The spin-phonon coupling is assumed to appear as a result of the modulation of the isotropic and antisymmetric (Dzyaloshinsky-Moriya) exchange interactions in the central triangular layer of vanadium ions by the acoustic lattice vibrations. The relaxation rates are estimated within the Debye model for the lattice vibrations. Within the pseudo-angular momentum representation the selection rules for the direct (one-phonon) transitions between Zeeman levels are derived and a special role of the antisymmetric exchange is underlined. The probabilities of the two-phonon Orbach-Aminov type processes are evaluated as well, while the Raman type relaxation is shown to have a negligible importance at low temperatures at which the Rabi oscillations have been detected.

Tarantul, Alex; Tsukerblat, Boris

2011-10-01

26

Excitation of the two-phonon giant dipole resonance in 238U studied via inclusive measurements of neutron-removal cross sections  

NASA Astrophysics Data System (ADS)

As part of a comprehensive study of uranium fragmentation at relativistic energies at the GSI projectile fragment separator, FRS, inclusive neutron-removal cross sections have been measured for several xn channels at projectile energies of 600 and 950 A MeV. The electromagnetic cross sections agree surprisingly well with a semiclassical calculation based on measured photonuclear cross sections and do not require an extra enhancement of the two-phonon giant dipole excitation as concluded from similar measurements with 197Au.

Aumann, T.; Sümmerer, K.; Bertulani, C. A.; Kratz, J. V.; Geissel, H.; Blank, B.; Brohm, T.; Clerc, H.-G.; Czajkowski, S.; Donzaud, C.; Grewe, A.; Hanelt, E.; Heinz, A.; Irnich, H.; de Jong, M.; Junghans, A.; Magel, A.; Münzenberg, G.; Nickel, F.; Pfützner, M.; Piechaczek, A.; Röhl, C.; Scheidenberger, C.; Schmidt, K.-H.; Schwab, W.; Steinhäuser, S.; Trinder, W.; Voss, B.; FRS-Collaboration

1996-02-01

27

Nature of One- and Two-Phonon Mixed Symmetry States in 92Zr and 94Mo from High-Resolution Electron and Proton Scattering  

SciTech Connect

High-resolution inelastic electron (performed at the S-DALINAC) and proton (performed at iThemba LABS) scattering experiments on 92Zr and 94Mo with emphasis on E2 transitions are presented The measured form factors and angular distributions provide a measure for the F-spin purity, respectively the isovector nature, of the proposed one-phonon mixed symmetry states and furthermore provide a sensitive test of a possible two-phonon character of excited 2+ states.

Neumann-Cosel, P. von; Burda, O.; Kuhar, M.; Lenhardt, A.; Ponomarev, V. Yu.; Richter, A.; Wambach, J. [Institut fuer Kernphysik, Technische Universitaet Darmstadt, D-64289 Darmstadt (Germany); Botha, N. T.; Fearick, R. W. [Physics Department, University of Cape Town, Rondebosch 7700 (South Africa); Carter, J.; Sideras-Haddad, E. [School of Physics, University of the Witwatersrand, Johannesburg 2050 (South Africa); Foertsch, S. V.; Neveling, R.; Smit, F. D. [iThemba LABS, PO Box 722, Somerset West 7129 (South Africa); Fransen, C. [Institut fuer Kernphysik, Universitaet zu Koeln, D-50937 Cologne (Germany); Fujita, H. [School of Physics, University of the Witwatersrand, Johannesburg 2050 (South Africa); iThemba LABS, PO Box 722, Somerset West 7129 (South Africa); Pietralla, N. [Department of Physics and Astronomy, SUNY, Stony Brook, NY 11794-3800 (United States)

2006-03-13

28

Fragmentation of low-lying dipole strength in the odd-mass nucleus {sup 133}Cs  

SciTech Connect

The fragmentation of low-lying dipole strength in the odd-mass nucleus {sup 133}Cs has been investigated in nuclear resonance fluorescence (NRF) experiments performed at the bremsstrahlung beam of the Stuttgart Dynamitron accelerator at an end-point energy of 4.1 MeV. In the excitation energy range 2.3 {endash} 3.7 MeV in total 22 new dipole excitations were observed. From the high-resolution {gamma}-ray spectra measured by three high-efficiency Ge detectors the reduced excitation probabilities B(E1){up_arrow} or B(M1){up_arrow} were deduced. The fragmentation and absolute total strengths of the detected dipole excitations are compared with results for the neighboring even-even, {gamma}-soft nucleus {sup 134}Ba, where both, rather strong {ital scissors mode-like} M1 and two-phonon E1 excitations are known from recent NRF experiments. {copyright} {ital 1997} {ital The American Physical Society}

Besserer, J.; Beck, O.; Eckert, T.; Jaeger, D.; Kneissl, U.; Margraf, J.; Maser, H.; Nord, A.; Pitz, H.H. [Institut fuer Strahlenphysik, Universitaet Stuttgart, Allmandring 3, D-70569 Stuttgart (Germany)] [Institut fuer Strahlenphysik, Universitaet Stuttgart, Allmandring 3, D-70569 Stuttgart (Germany); von Brentano, P.; Herzberg, R.; Pietralla, N.; Zilges, A. [Institut fuer Kernphysik, Universitaet zu Koeln, Zuelpicher Strasse 77, D-50937 Koeln (Germany)] [Institut fuer Kernphysik, Universitaet zu Koeln, Zuelpicher Strasse 77, D-50937 Koeln (Germany)

1997-09-01

29

Low-lying E1,M1, and E2 strength distributions in {sup 124,126,128,129,130,131,132,134,136}Xe: Systematic photon scattering experiments in the mass region of a nuclear shape or phase transition  

Microsoft Academic Search

Systematic nuclear resonance fluorescence (NRF) experiments on all nine stable (seven even-even and two odd-mass) Xe isotopes have been performed at the bremsstrahlung facility of the 4.3-MV Stuttgart Dynamitron accelerator. For the first time thin-walled, high-pressure gas targets (about 70 bar) with highly enriched target material were used in NRF experiments. Precise excitation energies, transition strengths, spins, and decay branching

H. von Garrel; U. Kneissl; C. Kohstall; H. H. Pitz; M. Scheck; F. Stedile; S. Walter; P. von Brentano; C. Fransen; G. Friessner; N. Hollmann; J. Jolie; A. Linnemann; D. Muecher; N. Pietralla; C. Scholl; V. Werner; F. Kaeppeler; K. Wisshak; L. Kaeubler

2006-01-01

30

Low-lying E1,M1, and E2 strength distributions in Xe124,126,128,129,130,131,132,134,136: Systematic photon scattering experiments in the mass region of a nuclear shape or phase transition  

Microsoft Academic Search

Systematic nuclear resonance fluorescence (NRF) experiments on all nine stable (seven even-even and two odd-mass) Xe isotopes have been performed at the bremsstrahlung facility of the 4.3-MV Stuttgart Dynamitron accelerator. For the first time thin-walled, high-pressure gas targets (about 70 bar) with highly enriched target material were used in NRF experiments. Precise excitation energies, transition strengths, spins, and decay branching

H. von Garrel; P. Von Brentano; C. Fransen; G. Friessner; N. Hollmann; J. Jolie; F. Käppeler; L. Käubler; U. Kneissl; C. Kohstall; L. Kostov; A. Linnemann; D. Mücher; N. Pietralla; H. H. Pitz; G. Rusev; M. Scheck; K. D. Schilling; C. Scholl; R. Schwengner; F. Stedile; S. Walter; V. Werner; K. Wisshak

2006-01-01

31

Weighted f-values, A-values, and line strengths for the E1 transitions among 3d{sup 6}, 3d{sup 5}4s, and 3d{sup 5}4p levels of Fe III  

SciTech Connect

Weighted oscillator strengths, weighted radiative rates, and line strengths for all the E1 transitions between 285 fine-structure levels belonging to the 3d{sup 6}, 3d{sup 5}4s, and 3d{sup 5}4p configurations of Fe III are presented, in ascending order of wavelength. Calculations have been undertaken using the general configuration interaction (CI) code CIV3. The large configuration set is constructed by allowing single and double replacements from any of 3d{sup 6}, 3d{sup 5}4s, 3d{sup 5}4p, and 3d{sup 5}4d configurations to nl orbitals with n{<=}5,l{<=}3 as well as 6p. Additional selective promotions from 3s and 3p subshells are also included in the CI expansions to incorporate the important correlation effects in the n=3 shell. Results of some strong transitions between levels of 3d{sup 6}, 3d{sup 5}4s, and 3d{sup 5}4p configurations are also presented and compared with other available calculations. It is found that large disagreements occur in many transitions among the existing calculations.

Deb, Narayan C. [School of Mathematics and Physics, Queen's University Belfast, Belfast BT7 1NN, Northern Ireland (United Kingdom); Hibbert, Alan [School of Mathematics and Physics, Queen's University Belfast, Belfast BT7 1NN, Northern Ireland (United Kingdom)], E-mail: a.hibbert@qub.ac.uk

2009-03-15

32

Dipole strength distributions in the stable Ba isotopes {sup 134-138}Ba: A study in the mass region of a nuclear shape transition  

SciTech Connect

The low-lying dipole strength distributions in the odd-mass isotopes {sup 135,137}Ba were studied in nuclear resonance fluorescence experiments (NRF) performed at the Stuttgart Dynamitron facility using bremsstrahlung beams with end point energies of 4.1, 3.1, and 2.5 MeV. Numerous excited states, most of them unknown so far, were observed in the excitation energy range up to 4 MeV. Detailed spectroscopic information has been obtained on excitation energies, decay widths, decay branching ratios, and transition probabilities. The results for {sup 137}Ba are compared with calculations in the framework of the Quasiparticle-Phonon Model. The new data for {sup 135,137}Ba complete the systematics of low-lying dipole excitations as observed for the even Ba isotopes {sup 134,136,138}Ba in previous NRF experiments in Stuttgart. The complete systematics within the Ba isotopic chain, exhibiting a nuclear shape transition, is discussed with respect to E1 two-phonon excitations, M1 scissors mode excitations, and in regard to the new critical point symmetries.

Scheck, M.; Garrel, H. von; Belic, D.; Kneissl, U.; Kohstall, C.; Nord, A.; Pitz, H.H.; Stedile, F. [Institut fuer Strahlenphysik, Universitaet Stuttgart, D-70569 Stuttgart (Germany); Tsoneva, N. [Institut fuer Theor. Physik, Universitaet Giessen, D-35392 Giessen (Germany); Brentano, P. von; Fransen, C.; Gade, A.; Jolie, J.; Linnemann, A.; Pietralla, N.; Werner, V. [Institut fuer Kernphysik, Universitaet zu Koeln, D-50937 Cologne (Germany); Stoyanov, C. [Institute for Nuclear Research and Nuclear Energy, 1784 Sofia (Bulgaria)

2004-10-01

33

Adenovirus E1A gene autorepression: revertants of an E1A promoter mutation encode altered E1A proteins.  

PubMed

Revertants have been isolated from Ad3hr15, a mutant of human adenovirus type 3 that carries a defective E1A promoter. Transcription of these revertant E1A genes is restored--from nil for Ad3hr15 mutant to levels exceeding that of the wild-type virus. The mutant Ad3hr15 virus and the revertants all have an aberrant E1A promoter that contains two short tandem duplications of viral DNA sequence. The E1A gene-coding region of the mutant is the same as that for wild-type adenovirus type 3, whereas the revertants are characterized by short in-frame deletions within the 5' exon region of their E1A genes. Location of these reverting, second-site deletions is discussed in relation to E1A gene autoregulation and the evolved diversity of E1A-related oncogenic potential among different human adenoviruses. PMID:2960973

Larsen, P L; Tibbetts, C

1987-12-01

34

Two-phonon absorption operator in spectroscopy  

NASA Astrophysics Data System (ADS)

While the raising operator a does not have eigenvectors, coherent states are eigenvectors of the lowering operator aˆ. Therefore, operating with the operator exp[ka] on coherent states poses a challenge, where k is an arbitrary constant. The result of this operation on coherent states has not yet been reported in a closed form. A closed-form expression for this problem is derived. The applicability and correctness of the result are tested by calculating the electronic dipole moment time correlation function and the corresponding Franck-Condon factors for systems with distorted Hamiltonian which arises in case of quadratic electron-phonon coupling which is significant in quantifying electronic dephasing.

Toutounji, Mohamad

2013-01-01

35

Determining the electron-phonon coupling strength from Resonant Inelastic X-ray Scattering at transition metal L-edges  

SciTech Connect

We show that high-resolution Resonant Inelastic X-ray Scattering (RIXS) provides direct, element-specific and momentum-resolved information on the electron-phonon (e-p) coupling strength. Our theoretical analysis indicates how the e-p coupling can be extracted from RIXS spectra by determining the differential phonon scattering cross-section. An alternative manner to extract the coupling is to use the one- and two-phonon loss ratio, which is governed by the e-p coupling strength and the core-hole lifetime. This allows the determination of the e-p coupling on an absolute energy scale.

Ament, L.J.P.; van Veenendaal, M.; van den Brink, J. (Leiden); (NIU); (IFW Dresden)

2012-04-02

36

Adenovirus-2 E1a and E1b gene products regulate enhancer mediated transcription.  

PubMed Central

We have shown that adenovirus-2 early region 1 gene products in trans and the SV40 enhancer in cis have an additive effect in stimulating transcription from adenovirus IVa2 and major late promoters (Natarajan, V. and Salzman, N. P., Nucleic Acids Research 13, 4067, 1985). In the present study, we show that both the E1a and E1b gene products are necessary for this stimulatory effect on enhancer mediated transcription. In the absence of E1b region, the transcription is strongly suppressed by E1a. Transcription from E1a promoter is also stimulated 4-5 fold in the presence of E1b region. The data suggest that 21K protein coded by the E1b region modulates transcription from the E1a promoter and the action of E1a gene products on transcription from other promoters. Images

Natarajan, V

1986-01-01

37

Strength Testing.  

ERIC Educational Resources Information Center

Postural deviations resulting from strength and flexibility imbalances include swayback, scoliosis, and rounded shoulders. Screening tests are one method for identifying strength problems. Tests for the evaluation of postural problems are described, and exercises are presented for the strengthening of muscles. (JN)

Londeree, Ben R.

1981-01-01

38

The ?-ray Strength Function in Nuclear Astrophysics  

NASA Astrophysics Data System (ADS)

The ?-ray strength function is a key statistical nuclear ingredient to the s-, r- and p-process nucleosynthesis of heavy elements. It has recently become apparent that extra ?-ray strengths that appear near neutron threshold on top of the low-energy tail of GDR play an important role in neutron capture and photodisintegration. We discuss extra ?-ray strengths of pigmy E1 and giant M1 nature based on the latest experimental photoneutron cross sections measured with laser Compton scattering ?-rays.

Utsunomiya, H.; Akimune, H.; Yamagata, T.; Kondo, T.; Kamata, M.; Itoh, O.; Toyokawa, H.; Yamada, K.; Matsumoto, T.; Harada, H.; Kitatani, F.; Goko, S.; Goriely, S.; Hilaire, S.; Koning, A. J.

2009-05-01

39

Spaghetti Strength  

NSDL National Science Digital Library

In this activity on page 7 of the PDF, learners explore how engineers characterize building materials. Learners test the strength of spaghetti and determine how the number of spaghetti strands affects the strength of a bundle of spaghetti. Use this activity to chemical bonds, mechanical testing, and engineering. Note: The pasta strands can be dipped in water and stuck together to more closely mimic the layers within a piece of plywood. More information about this can be found at the top of page 7, directly underneath the cartoon image. Safety note: Do not eat or drink any of the materials in this activity.

Society, American C.

2011-01-01

40

CYP2E1 Substrate Inhibition  

PubMed Central

In this study we offer a mechanistic interpretation of the previously known but unexplained substrate inhibition observed for CYP2E1. At low substrate concentrations, p-nitrophenol (pNP) was rapidly turned over (47 min?1) with relatively low Km (24 ?M); nevertheless, at concentrations of >100 ?M, the rate of pNP oxidation gradually decreased as a second molecule bound to CYP2E1 through an effector site (Kss = 260 ?M), which inhibited activity at the catalytic site. 4-Methylpyrazole (4MP) was a potent inhibitor for both sites through a mixed inhibition mechanism. The Ki for the catalytic site was 2.0 ?M. Although we were unable to discriminate whether an EIS or ESI complex formed, the respective inhibition constants were far lower than Kss. Bicyclic indazole (IND) inhibited catalysis through a single CYP2E1 site (Ki = 0.12 ?M). Similarly, 4MP and IND yielded type II binding spectra that reflected the association of either two 4MP or one IND molecule(s) to CYP2E1, respectively. Based on computational docking studies with a homology model for CYP2E1, the two sites for monocyclic molecules, pNP and 4MP, exist within a narrow channel connecting the active site to the surface of the enzyme. Because of the presence of the heme iron, one site supports catalysis, whereas the other more distal effector site binds molecules that can influence the binding orientation and egress of molecules for the catalytic site. Although IND did not bind these sites simultaneously, the presence of IND at the catalytic site blocked binding at the effector site.

Collom, Samuel L.; Laddusaw, Ryan M.; Burch, Amber M.; Kuzmic, Petr; Perry, Martin D.; Miller, Grover P.

2014-01-01

41

26 CFR 1.367(e)-1 - Distributions described in section 367(e)(1).  

...persons. Paragraph (c) of this section...persons. Paragraph (e) of this section...provided in paragraph (c) of this section...under section 367(e)(1). A distributing...where section 897(e)(1) and the regulations...distribution. (c) Nonrecognition...

2014-04-01

42

26 CFR 1.367(e)-1 - Distributions described in section 367(e)(1).  

Code of Federal Regulations, 2012 CFR

...persons. Paragraph (c) of this section...persons. Paragraph (e) of this section...provided in paragraph (c) of this section...under section 367(e)(1). A distributing...where section 897(e)(1) and the regulations...distribution. (c) Nonrecognition...

2012-04-01

43

26 CFR 1.367(e)-1 - Distributions described in section 367(e)(1).  

Code of Federal Regulations, 2013 CFR

...persons. Paragraph (c) of this section...persons. Paragraph (e) of this section...provided in paragraph (c) of this section...under section 367(e)(1). A distributing...where section 897(e)(1) and the regulations...distribution. (c) Nonrecognition...

2013-04-01

44

26 CFR 1.367(e)-1 - Distributions described in section 367(e)(1).  

Code of Federal Regulations, 2011 CFR

...persons. Paragraph (c) of this section...persons. Paragraph (e) of this section...provided in paragraph (c) of this section...under section 367(e)(1). A distributing...where section 897(e)(1) and the regulations...distribution. (c) Nonrecognition...

2011-04-01

45

26 CFR 1.367(e)-1 - Distributions described in section 367(e)(1).  

Code of Federal Regulations, 2010 CFR

...persons. Paragraph (c) of this section...persons. Paragraph (e) of this section...provided in paragraph (c) of this section...under section 367(e)(1). A distributing...where section 897(e)(1) and the regulations...distribution. (c) Nonrecognition...

2010-04-01

46

Identification of the E1fE1k cholinesterase genotype.  

PubMed Central

A family segregating for the A, F, and K alleles at cholinesterase locus 1 is described. This work, undertaken after the proband suffered prolonged apnoea after the use of suxamethonium during the delivery of her third child, resulted in the identification of the E1fE1k genotype in her oldest son.

Burgess, A M

1988-01-01

47

Cesium Line Strengths by Absorption  

Microsoft Academic Search

We are studying the low-lying electronic states of atomic cesium because of their importance to the interpretation of atomic parity nonconservation measurements. Precision measurements of E1 transition line strengths test the behavior of theoretical atomic structure calculations especially at large radii. We measure the absorption spectrum of laser light as the laser frequency is scanned through the 6s ^2S_1\\/2---7p ^2P_J

Carol E. Tanner; Robert J. Rafac

2001-01-01

48

Impact of E1 and Cre on adenovirus vector amplification: developing MDCK CAV-2-E1 and E1-Cre transcomplementing cell lines.  

PubMed

Adenovirus vectors have been extensively studied through the manipulation of viral genome. However, little attention is being paid to their producer cell-lines; cells are selected according to virus yields, neglecting the expression profile of transcomplementing gene products underlying cell performance. This work evaluates the impact of E1 (E1A and E1B) and Cre recombinase levels in the production of E1-deleted and helper-dependent canine adenovirus type 2 (CAV-2) vectors using MDCK cells. E1A and E1B gene expression and Cre activity were evaluated in different cell clones and compared with the corresponding cell productivity and susceptibility to oxidative stress injury. CAV-2 production was proportional to E1A expression (the highest levels of E1A corresponding to productivities of 3000-5000 I.P./cell), while E1B prolonged host cell viability after infection, conferring protection against apoptosis. Cre recombinase counteracted E1B anti-apoptotic properties, however viral production was maintained under high levels of Cre. Yet, Cre recombinase side effects can be reduced using cell lines with lower Cre-activities, without compromising the excision efficiency of helper vector packaging signal. These results highlight the influence of transcomplementing gene products on CAV-2 producer cell line performance, and the ability to express high levels of E1A and E1B as an important feature for cell line establishment and high adenovirus titers. PMID:23565229

Fernandes, Paulo; Santiago, Virgínia M; Rodrigues, Ana F; Tomás, Hélio; Kremer, Eric J; Alves, Paula M; Coroadinha, Ana S

2013-01-01

49

Application of Strength Diagnosis.  

ERIC Educational Resources Information Center

Discusses the various strength qualities (maximum strength, high- and low-load speed strength, reactive strength, rate of force development, and skill performance), noting why a training program design based on strength diagnosis can lead to greater efficacy and better performance gains for the athlete. Examples of tests used to assess strength

Newton, Robert U.; Dugan, Eric

2002-01-01

50

'Dirac Fock + core-polarization' calculations of E1 transitions in the francium isoelectronic sequence  

Microsoft Academic Search

Some E1 transitions in the francium isoelectronic sequence are computed in the 'Dirac-Fock + core-polarization' approximation, where core-valence electron correlation is treated in a semiclassical core-polarization picture. The obtained ionization energies and oscillator strengths are tested versus very accurate many-body perturbation treatment (MBPT) theoretical results published recently as well as versus available experimental data. The role of core-valence correlation (core

Jacek Migdalek; Agnieszka Glowacz-Proszkiewicz

2007-01-01

51

26 CFR 1.665(e)-1 - Preceding taxable year.  

Code of Federal Regulations, 2010 CFR

...2013-04-01 false Preceding taxable year. 1.665(e)-1 Section 1...Distributions of Trusts Applicable to Taxable Years Beginning Before January 1, 1969 § 1.665(e)-1 Preceding taxable year. (a) Definition. For...

2013-04-01

52

Study of M1 and E1 excitations by high-resolution proton inelastic scattering measurement at forward angles  

SciTech Connect

Experimental technique for measuring proton inelastic scattering with high-resolution at 295 MeV and at forward angles including zero degrees is described. The method is useful for extracting spin part of the M1 strength via nuclear excitation as well as E1 strength via Coulomb excitation. An excitation energy resolution of 20 keV, good scattering angle resolution, and low background condition have been achieved. The experimental technique was applied for several sd and pf shell nuclei.

Tamii, A.; Adachi, T.; Hatanaka, K.; Hashimoto, H.; Kaneda, T.; Matsubara, H.; Okamura, H.; Sakemi, Y.; Shimizu, Y.; Tameshige, Y.; Yosoi, M. [Research Center for Nuclear Physics, 10-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan); Carter, J. [Univ. of the Witwatersrand, Johannesburg 2050 (South Africa); Dozono, M. [Dep. of Physics, Kyushu Univ, Higashi, Fukuoka 812-8581 (Japan); Fujita, H. [Univ. of the Witwatersrand, Johannesburg 2050 (South Africa); iThemba LABS, Somerset West 7129 (South Africa); Fujita, Y. [Dep. of Physics, Osaka Univ., 1-1 Machikaneyama, Toyonaka, Osaka 560-0043 (Japan); Itoh, M. [Cyclotron and Radioisotope Center, Tohoku Univ., Sendai, Miyagi 980-8578 (Japan); Kawabata, T.; Nakanishi, K.; Sasamoto, Y. [Center for Nuclear Study, Univ. of Tokyo, Bunkyo, Tokyo 113-0033 (Japan); Neumann-Cosel, P. von [Institute fuer Kernphysik TU Darmstadt, 64289 Darmstadt (Germany)] (and others)

2007-06-13

53

Why Strength Training?  

MedlinePLUS

... Physical Activity Physical Activity Share Compartir Why strength training? Research has shown that strengthening exercises are both ... person's mental and emotional health. Benefits of Strength Training There are numerous benefits to strength training regularly, ...

54

Structure of a ubiquitin E1-E2 complex: insights to E1-E2 thioester transfer  

PubMed Central

Summary Ubiquitin (Ub) conjugation is initiated by an E1 enzyme that catalyzes carboxy-terminal Ub adenylation, thioester bond formation to a catalytic cysteine in the E1 Cys domain and thioester transfer to a catalytic cysteine in E2 conjugating enzymes. How the E1 and E2 active sites come together during thioester transfer and how Ub E1 interacts with diverse Ub E2s remains unclear. Here we present a crystal structure of a Ub E1-E2(Ubc4)/Ub/ATP·Mg complex that was stabilized by inducing a disulfide bond between the E1 and E2 active sites. The structure reveals combinatorial recognition of the E2 by the E1 ubiquitin-fold domain (UFD) and Cys domain and mutational analysis, coupled with thioester transfer assays using E1, Ubc4 and other Ub E2s, show that both interfaces are important for thioester transfer. Comparison to a Ub E1/Ub/ATP·Mg structure reveals conformational changes in the E1 that bring the E1 and E2 active sites together.

Olsen, Shaun K.; Lima, Christopher D.

2013-01-01

55

Strength Coefficient of Materials.  

National Technical Information Service (NTIS)

South Dakota's, previously conducted, Flexible Pavement Study indicated a relationship between Strength and Effective Thickness. It was apparent that a simple slope formula used for any two points on the curve produced strength coefficients. The slope of ...

R. A. Crawford

1971-01-01

56

Strength Modeling Report  

NASA Technical Reports Server (NTRS)

Strength modeling is a complex and multi-dimensional issue. There are numerous parameters to the problem of characterizing human strength, most notably: (1) position and orientation of body joints; (2) isometric versus dynamic strength; (3) effector force versus joint torque; (4) instantaneous versus steady force; (5) active force versus reactive force; (6) presence or absence of gravity; (7) body somatotype and composition; (8) body (segment) masses; (9) muscle group envolvement; (10) muscle size; (11) fatigue; and (12) practice (training) or familiarity. In surveying the available literature on strength measurement and modeling an attempt was made to examine as many of these parameters as possible. The conclusions reached at this point toward the feasibility of implementing computationally reasonable human strength models. The assessment of accuracy of any model against a specific individual, however, will probably not be possible on any realistic scale. Taken statistically, strength modeling may be an effective tool for general questions of task feasibility and strength requirements.

Badler, N. I.; Lee, P.; Wong, S.

1985-01-01

57

Establishment of Class e1 Mass Standard of 50 kg  

NASA Astrophysics Data System (ADS)

Because of the equipment limit, the dissemination of large mass has been realized by a large amount of higher class of 20 kg weights since 1950s in China. But with improvement of the technique and customer's requirements, it is necessary to establish the mass standard of 50 kg weight. In 1990s, mass standard laboratory has set up Class E1 weight sets from 20 kg to 1 mg. To extend the mass capacity up to 50 kg of Class E1, it is not only to produce Class E1 50 kg weight and import a mass comparator, but also need to lift the heavy weight from weight box to balance receptor safely. Up to now, the mass comparator has been installed in Hepingli campus of NIM. Two pieces of Class E1 50 kg weights are determined by combination weighing method. A lifting device has been mounted close to the mass comparator in order to move the 50 kg easily.

Yao, Hong; Wang, Jian; Ding, Jingan; Zhong, Ruilin; Ren, Xiaoping

58

CYP2E1 hydroxylation of aniline involves negative cooperativity.  

PubMed

CYP2E1 plays a role in the metabolic activation and elimination of aniline, yet there are conflicting reports on its mechanism of action, and hence relevance, in aniline metabolism. Based on our work with similar compounds, we hypothesized that aniline binds two CYP2E1 sites during metabolism resulting in cooperative reaction kinetics and tested this hypothesis through rigorous in vitro studies. The kinetic profile for recombinant CYP2E1 demonstrated significant negative cooperativity based on a fit of data to the Hill equation (n=0.56). Mechanistically, the data were best explained through a two-binding site cooperative model in which aniline binds with high affinity (K(s)=30 ?M) followed by a second weaker binding event (K(ss)=1100 uM) resulting in a threefold increase in the oxidation rate. Binding sites for aniline were confirmed by inhibition studies with 4-methylpyrazole. Inhibitor phenotyping experiments with human liver microsomes validated the central role for CYP2E1 in aniline hydroxylation and indicated minor roles for CYP2A6 and CYP2C9. Importantly, inhibition of minor metabolic pathways resulted in a kinetic profile for microsomal CYP2E1 that replicated the preferred mechanism and parameters observed with the recombinant enzyme. Scaled modeling of in vitro CYP2E1 metabolism of aniline to in vivo clearance, especially at low aniline levels, led to significant deviations from the traditional model based on non-cooperative, Michaelis-Menten kinetics. These findings provide a critical mechanistic perspective on the potential importance of CYP2E1 in the metabolic activation and elimination of aniline as well as the first experimental evidence of a negatively cooperative metabolic reaction catalyzed by CYP2E1. PMID:24345333

Hartman, Jessica H; Knott, Katie; Miller, Grover P

2014-02-01

59

Isovector dipole strength in nuclei with extreme neutron excess  

SciTech Connect

The E1 strength is systematically analyzed in very neutron-rich Sn nuclei, beyond {sup 132}Sn until {sup 166}Sn, within the relativistic quasiparticle random phase approximation. The great neutron excess favors the appearance of a deformed ground state for {sup 142-162}Sn. The evolution of the low-lying strength in deformed nuclei is determined by the interplay of two factors, isospin asymmetry and deformation: while greater neutron excess increases the total low-lying strength, deformation hinders and spreads it. Very neutron rich deformed nuclei may not be as good candidates as spherical nuclei like {sup 132}Sn for the experimental study of low-lying E1 strength.

Arteaga, D. Pena; Khan, E. [Institut de Physique Nucleaire, Universite Paris-Sud, IN2P3-CNRS, F-91406 Orsay Cedex (France); Ring, P. [Physikdepartment, Technische Universitaet Muenchen, D-85748 Garching (Germany)

2009-03-15

60

Shell-model study of electric dipole and spin-dipole strengths in 11Li  

NASA Astrophysics Data System (ADS)

We have studied electric dipole (E1) and spin-dipole strength distribution in 11Li by shell model calculations with halo effect. Two peaks in the E1 strength are found in the low excitation energy region below Ex=4 MeV, which have almost the same energies as observed E1 peaks in the Coulomb breakup reaction of 11Li. The calculated E1 strength up to Ex=4 MeV exhaust about 4% of the Thomas-Reiche-Kuhn energy-weighted sum rule value. We found also pigmy and giant peaks in spin-dipole strengths of 11Li. Possible existence of double soft dipole mode and giant resonance built on the soft dipole states are investigated.

Suzuki, Toshio; Sagawa, H.; Bortignon, P. F.

2000-01-01

61

Isoscalar electric multipole strength in 12C  

NASA Astrophysics Data System (ADS)

The excitation region in 12C below Ex=45 MeV was studied using 240 MeV ?-particle scattering. Elastic scattering was measured from ?c.m.=3.8° to 49.4° and density dependant folding optical model parameters were obtained. Inelastic scattering to the 4.44 MeV 2+, 7.65 MeV 0+, 9.64 MeV 3-, 10.3 MeV 0+, and 10.84 MeV 1- states was measured and B(EL) values obtained. Inelastic scattering exciting 12C to 10 MeV?Ex?12.5 MeV was measured from 1.4°??c.m.?10° and to 12.5 MeV?Ex?45 MeV from 1.4°??c.m.?16° and E0, E1, E2, and E3 strength distributions were obtained. Strength was identified corresponding to 27±5, 78±9, and 51±7% of the isoscalar E0, E1, and E2 energy weighted sum rule (EWSR), respectively, with centroids of 21.9±0.3, 27.5±0.4, and 22.6±0.5 MeV and rms widths of 4.8±0.5, 7.6±0.6, and 6.8±0.6 MeV. Less than 7% of the E3 EWSR strength was identified.

John, Bency; Tokimoto, Y.; Lui, Y.-W.; Clark, H.; Chen, X.; Youngblood, D.

2003-07-01

62

Character Strengths Among Youth  

Microsoft Academic Search

Four hundred and fiftynine students from 20 different high school classrooms in Michigan participated in focus group discussions about the character strengths included in the Values in Action Classifi- cation. Students were interested in the subject of good character and able to discuss with candor and sophistication instances of each strength. They were especially drawn to the positive traits of

Tracy A. Steen; Lauren V. Kachorek; Christopher Peterson

2003-01-01

63

Recognizing Neglected Strengths  

ERIC Educational Resources Information Center

To identify diverse student strengths and to learn how teachers can build instruction on those strengths, the author and his colleagues have conducted multiple studies among students in Alaska, the mainland United States, Kenya, and other countries. In a series of studies in Alaska and Kenya, the researchers measured the adaptive cultural…

Sternberg, Robert J.

2006-01-01

64

High strength, superplastic superalloy  

NASA Technical Reports Server (NTRS)

High strength superplastic superalloys are produced by extruding a pre-alloyed powder. The cast nickel base superalloy was remelted and converted to pre-alloyed powder by inert gas atomization. The superalloy shows high tensile strength and superplasticity and finds use in hot working and casting.

Ashbrook, R. L.; Freche, J. C.; Waters, W. J.

1969-01-01

65

Acetaldehyde and parkinsonism: role of CYP450 2E1  

PubMed Central

The present review update the relationship between acetaldehyde (ACE) and parkinsonism with a specific focus on the role of P450 system and CYP 2E1 isozyme particularly. We have indicated that ACE is able to enhance the parkinsonism induced in mice by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, a neurotoxin able to damage the nigrostriatal dopaminergic pathway. Similarly diethyldithiocarbamate, the main metabolite of disulfiram, a drug widely used to control alcoholism, diallylsulfide (DAS) and phenylisothiocyanate also markedly enhance the toxin-related parkinsonism. All these compounds are substrate/inhibitors of CYP450 2E1 isozyme. The presence of CYP 2E1 has been detected in the dopamine (DA) neurons of rodent Substantia Nigra (SN), but a precise function of the enzyme has not been elucidated yet. By treating CYP 2E1 knockout (KO) mice with the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, the SN induced lesion was significantly reduced when compared with the lesion observed in wild-type animals. Several in vivo and in vitro studies led to the conclusion that CYP 2E1 may enhance the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine toxicity in mice by increasing free radical production inside the dopaminergic neurons. ACE is a good substrate for CYP 2E1 enzyme as the other substrate-inhibitors and by this way may facilitate the susceptibility of dopaminergic neurons to toxic events. The literature suggests that ethanol and/or disulfiram may be responsible for toxic parkinsonism in human and it indicates that basal ganglia are the major targets of disulfiram toxicity. A very recent study reports that there are a decreased methylation of the CYP 2E1 gene and increased expression of CYP 2E1 mRNA in Parkinson's disease (PD) patient brains. This study suggests that epigenetic variants of this cytochrome contribute to the susceptibility, thus confirming multiples lines of evidence which indicate a link between environmental toxins and PD.

Vaglini, Francesca; Viaggi, Cristina; Piro, Valentina; Pardini, Carla; Gerace, Claudio; Scarselli, Marco; Corsini, Giovanni Umberto

2013-01-01

66

Incrimination of Heterogeneous Nuclear Ribonucleoprotein E1 (hnRNP-E1) as a Candidate Sensor of Physiological Folate Deficiency*  

PubMed Central

The mechanism underlying the sensing of varying degrees of physiological folate deficiency, prior to adaptive optimization of cellular folate uptake through the translational up-regulation of folate receptors (FR) is unclear. Because homocysteine, which accumulates intracellularly during folate deficiency, stimulated interactions between heterogeneous nuclear ribonucleoprotein E1 (hnRNP-E1) and an 18-base FR-? mRNA cis-element that led to increased FR biosynthesis and net up-regulation of FR at cell surfaces, hnRNP-E1 was a plausible candidate sensor of folate deficiency. Accordingly, using purified components, we evaluated the physiological basis whereby l-homocysteine triggered these RNA-protein interactions to stimulate FR biosynthesis. l-Homocysteine induced a concentration-dependent increase in RNA-protein binding affinity throughout the range of physiological folate deficiency, which correlated with a proportionate increase in translation of FR in vitro and in cultured human cells. Targeted reduction of newly synthesized hnRNP-E1 proteins by siRNA to hnRNP-E1 mRNA reduced both constitutive and l-homocysteine-induced rates of FR biosynthesis. Furthermore, l-homocysteine covalently bound hnRNP-E1 via multiple protein-cysteine-S-S-homocysteine mixed disulfide bonds within K-homology domains known to interact with mRNA. These data suggest that a concentration-dependent, sequential disruption of critical cysteine-S-S-cysteine bonds by covalently bound l-homocysteine progressively unmasks an underlying RNA-binding pocket in hnRNP-E1 to optimize interaction with FR-? mRNA cis-element preparatory to FR up-regulation. Collectively, such data incriminate hnRNP-E1 as a physiologically relevant, sensitive, cellular sensor of folate deficiency. Because diverse mammalian and viral mRNAs also interact with this RNA-binding domain with functional consequences to their protein expression, homocysteinylated hnRNP-E1 also appears well positioned to orchestrate a novel, nutrition-sensitive (homocysteine-responsive), posttranscriptional RNA operon in folate-deficient cells.

Tang, Ying-Sheng; Khan, Rehana A.; Zhang, Yonghua; Xiao, Suhong; Wang, Mu; Hansen, Deborah K.; Jayaram, Hiremagalur N.; Antony, Asok C.

2011-01-01

67

Multi-Laboratory Validation of Estrone (E1) ELISA Methods  

EPA Science Inventory

This project is a round-robin evaluation of commercially available Enzyme-Linked Immunosorbent Assay (ELISA) technology to quantitatively or qualitatively measure the hormone estrone (E1) in combined animal feeding operation (CAFO) receiving streams. ELISA is meant to be a simpl...

68

Na(+) transport, and the E(1)P-E(2)P conformational transition of the Na(+)/K(+)-ATPase.  

PubMed Central

We have used admittance analysis together with the black lipid membrane technique to analyze electrogenic reactions within the Na(+) branch of the reaction cycle of the Na(+)/K(+)-ATPase. ATP release by flash photolysis of caged ATP induced changes in the admittance of the compound membrane system that are associated with partial reactions of the Na(+)/K(+)-ATPase. Frequency spectra and the Na(+) dependence of the capacitive signal are consistent with an electrogenic or electroneutral E(1)P <--> E(2)P conformational transition which is rate limiting for a faster electrogenic Na(+) dissociation reaction. We determine the relaxation rate of the rate-limiting reaction and the equilibrium constants for both reactions at pH 6.2-8.5. The relaxation rate has a maximum value at pH 7.4 (approximately 320 s(-1)), which drops to acidic (approximately 190 s(-1)) and basic (approximately 110 s(-1)) pH. The E(1)P <--> E(2)P equilibrium is approximately at a midpoint position at pH 6.2 (equilibrium constant approximately 0.8) but moves more to the E(1)P side at basic pH 8.5 (equilibrium constant approximately 0.4). The Na(+) affinity at the extracellular binding site decreases from approximately 900 mM at pH 6.2 to approximately 200 mM at pH 8.5. The results suggest that during Na(+) transport the free energy supplied by the hydrolysis of ATP is mainly used for the generation of a low-affinity extracellular Na(+) discharge site. Ionic strength and lyotropic anions both decrease the relaxation rate. However, while ionic strength does not change the position of the conformational equilibrium E(1)P <--> E(2)P, lyotropic anions shift it to E(1)P.

Babes, A; Fendler, K

2000-01-01

69

Strength Coefficient of Materials.  

National Technical Information Service (NTIS)

The study investigates the relationship of strength to thickness and type of material for six different construction materials; two bituminous paving materials, the same two aggregates without asphalt and two gravels typical of those normally used for bas...

R. A. Crawford D. W. Anderson

1973-01-01

70

Crew Strength Training  

NASA Video Gallery

Train to develop your upper and lower body strength in your muscles and bones by performing body-weight squats and push-ups.The Train Like an Astronaut project uses the excitement of exploration to...

71

Strength Distribution in Paper.  

National Technical Information Service (NTIS)

Tensile strength distributions are studied in four papers samples that exhibit a variety of brittle-to-ductile properties. 1005 tensile specimens were measured in each case. The standard Gumbel and Weibull distributions, and a recently proposed double exp...

M. J. Korteoja L. I. Salminen K. J. Niskanen M. Alava

1997-01-01

72

E1 resonances in neutron-rich nuclei within the phonon damping model  

NASA Astrophysics Data System (ADS)

The quasiparticle representation of the phonon damping model (PDM) is developed to include the superfluid pairing correlations microscopically. The formalism is applied to calculate the photoabsorption and the electromagnetic (EM) differential cross sections of E1 excitations in neutron-rich oxygen and calcium isotopes. The calculated photoabsorption cross sections agree reasonably well with the available data for 16,18O and 40,48 Ca. The results of calculations show that the change of the fraction of the E1 integrated strength in the region of pygmy dipole resonance (PDR) as a function of mass number A with increasing neutron number N is in agreement with the recent experimental data, and does not follow the prediction by the simple cluster model. The EM differential cross sections obtained within PDM in this work show prominent PDR peaks below 15 MeV for 20,22O in agreement with the recent experimental observation. It is also shown that, using low-energy RI beams at around 50--60 MeV/nucleon, one can observe clean and even enhanced PDR peaks without the admixture with the GDR in the EM differential cross sections of neutron-rich nuclei.

Dang, Nguyen Dinh; Au, Vuong Kim; Suzuki, Toshio; Arima, Akito

2001-08-01

73

Electron impact collision strengths in Sn XXIII  

SciTech Connect

The energy levels, multipole (E1, M1, E2, and M2) transition rates, and electron-impact collision strengths are calculated for Sn XXIII. The data refer to 107 fine-structure levels belonging to the configurations (1s{sup 2}2s{sup 2}2p{sup 6})3s{sup 2}3p{sup 6}3d{sup 10}, 3s{sup 2}3p{sup 6}3d{sup 9}4l, 3s{sup 2}3p{sup 5}3d{sup 10}4l, and 3s3p{sup 6}3d{sup 10}4l(l = s, p, d, and f). The collision strengths are calculated with a 20-collision-energy grid in terms of the energy of the scattered electron between 37.5 and 8436 eV by using the distorted-wave approximation. Effective collision strengths are obtained at five electron temperatures, T{sub e} (eV) = 193.89, 387.78, 581.67, 775.57, and 969.46, by integrating the collision strengths over a Maxwellian electron distribution.

Liang, Y.Q. [School of Logistics, Beijing Wuzi University, Beijing 101149 (China)], E-mail: yaqiongliang@hotmail.com; Zhong, J.Y. [National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)

2008-11-15

74

Proton decay of isolated E1 resonances with “abnormal” isospin  

Microsoft Academic Search

Qualitative analysis of partial proton and elastic radiation widths of isolated E1 resonances with “abnormal” spin has been carried out within the semimicroscopic approach based on the random phase approximation\\u000a with exact consideration of the single-particle continuum (continuum random phase approximation, CRPA). The results of the\\u000a calculations for such resonances in the 90Zr nucleus are compared with the available experimental

I. V. Safonov; M. L. Gorelik; M. G. Urin

2007-01-01

75

Molecular dynamics simulations of CYP2E1.  

PubMed

CYP2E1, as a member of the cytochrome P450s (CYPs) super-family, is in charge of six percent drug metabolism involving a diversity of drugs distinct in structures and chemical properties, such as alcohols, monocyclic compounds (e.g., acetaminophen, benzene, p-nitrophenol), bicyclic heterocycles (e.g., coumarin, caffeine) and even fatty acids. The aromatic molecules form a vital species catalyzed by CYP2E1. To investigate the mechanism of metabolizing a diversity of aromatic molecules, five representative aromatic substrates were selected: (1) benzene, the non-polar simple ring; (2) aniline, the monocyclic substrate with smallest substitution on the phenyl ring; (3) acetaminophen, a large monocyclic substrate with highly active reactivity; (4) chlorzoxazone, and (5) theophylline, the bicyclic substrates with low or high catalytic activities. They were docked into X-ray structure of CYP2E1, after which all-atom molecular dynamics simulations of 5 ns were performed on each model. It was found that the active site interact with the aromatic substrates mainly through ?-? stacking, supplied by five hydrophobic phenylalanines in the active site. Our simulations also illustrated the specific movement of different kinds of aromatic substrates in the pocket. Small monocyclic substrates show highly frequent self-rotation and limited translation movement. Substrates with single catalytic position are less movable in the pocket than substrates with multiple products. All these findings are quite useful for understanding the catalytic mechanism of CYP2E1, stimulating novel strategies for conducting further mutagenesis studies for specific drug design. PMID:22385180

Li, Jue; Wei, Dong-Qing; Wang, Jing-Fang; Yu, Zheng-Tian; Chou, Kuo-Chen

2012-03-01

76

A simple method for the simultaneous detection of E1A and E1B in adenovirus stocks.  

PubMed

Recombinant adenoviral vectors have been developed for use as therapeutic agents and for the introduction of exogenous genes into living cells. However, the occurrence of replication-competent adenoviruses (RCA) in adenovirus stocks produced in 293 cells remains a major problem in terms of the safe use of such vectors. To overcome the problems associated with the occurrence of RCA, we have established a simple method for the simultaneous detection of amplified E1A and E1B from RCA that might contaminate adenoviral stocks. The products amplified by polymerase chain reaction (PCR) were fractionated by regular electrophoresis on agarose gels and visualized by staining with ethidium bromide. This method is rapid and inexpensive for detection of RCA in the preparation of adenoviruses. PMID:14654922

Suzuki, Erika; Murata, Takehide; Watanabe, Sanae; Kujime, Yukari; Hirose, Megumi; Pan, Jianzhi; Yamazaki, Takahito; Ugai, Hideyo; Yokoyama, Kazunari K

2004-01-01

77

Radiative strength in the compound nucleus 157Gd  

NASA Astrophysics Data System (ADS)

The distribution of E1 and M1 strength in 157Gd compound nucleus has been studied. An investigation of capture of 2 and 24 keV neutrons in a 156Gd target resulted in resonance-averaged intensities of primary gamma rays between 3.7 and 6.4 MeV. From these intensities the gamma-ray strength functions have been derived for E1 and M1 radiation. We compare several formulations of strength functions to these resonance capture and/or photoabsorption data. Further we use these prescriptions in calculations of the total average radiation width, radiative capture cross sections, and gamma-ray spectra, and compare them to available experimental information. By analyzing these results strong evidence was found for an E1 strength function which is based on a generalized Lorentzian, enhanced compared to spherical nuclei, with an energy-dependent spreading width and a nonzero limit as the energy tends to zero. For M1 radiation the giant resonance spin-flip mode is favored.

Kopecky, J.; Uhl, M.; Chrien, R. E.

1993-01-01

78

Radiative strength in the compound nucleus [sup 157]Gd  

SciTech Connect

The distribution of [ital E]1 and [ital M]1 strength in [sup 157]Gd compound nucleus has been studied. An investigation of capture of 2 and 24 keV neutrons in a [sup 156]Gd target resulted in resonance-averaged intensities of primary gamma rays between 3.7 and 6.4 MeV. From these intensities the gamma-ray strength functions have been derived for [ital E]1 and [ital M]1 radiation. We compare several formulations of strength functions to these resonance capture and/or photoabsorption data. Further we use these prescriptions in calculations of the total average radiation width, radiative capture cross sections, and gamma-ray spectra, and compare them to available experimental information. By analyzing these results strong evidence was found for an [ital E]1 strength function which is based on a generalized Lorentzian, enhanced compared to spherical nuclei, with an energy-dependent spreading width and a nonzero limit as the energy tends to zero. For [ital M]1 radiation the giant resonance spin-flip mode is favored.

Kopecky, J. (Netherlands Energy Research Foundation ECN, P.O. Box 1, 1755 ZG Petten (Netherlands)); Uhl, M. (Institute fuer Radiumforschung und Kernphysik, Universitaet Wien, Boltzmanngasse 5, Wien (Austria)); Chrien, R.E. (Brookhaven National Laboratory, Upton, New York 11973 (United States))

1993-01-01

79

Strength of inorganic glass  

SciTech Connect

This book presents information on the following topics: a look at the history of glass strength; atomistic theory of fracture; surface chemistry in relation to the strength and fracture of silicate glasses; high-speed photographic investigations of the dynamic localized loading of some oxide glasses; a correction for measurements of contact area using Newton's rings; envionmentally enhanced crack growth; fatigue in glass; behavior of flaws in fused silica fibers; fracture toughness of chalcogenide glasses and glass-ceramics; fracture analysis of glass surfaces; and fracture mechanics parameters for glasses - a compilation and correlation.

Kurkjian, C.R.

1985-01-01

80

High strength alloys  

DOEpatents

High strength metal alloys are described herein. At least one composition of a metal alloy includes chromium, nickel, copper, manganese, silicon, niobium, tungsten and iron. System, methods, and heaters that include the high strength metal alloys are described herein. At least one heater system may include a canister at least partially made from material containing at least one of the metal alloys. At least one system for heating a subterranean formation may include a tubular that is at least partially made from a material containing at least one of the metal alloys.

Maziasz, Phillip James [Oak Ridge, TN; Shingledecker, John Paul [Knoxville, TN; Santella, Michael Leonard [Knoxville, TN; Schneibel, Joachim Hugo [Knoxville, TN; Sikka, Vinod Kumar [Oak Ridge, TN; Vinegar, Harold J [Bellaire, TX; John, Randy Carl [Houston, TX; Kim, Dong Sub [Sugar Land, TX

2010-08-31

81

Complete Electric Dipole Strength and Neutron Skin in 208Pb  

NASA Astrophysics Data System (ADS)

Small-angle polarized proton scattering including 0° on 208Pb has been studied at the RCNP cyclotron with high energy resolution of the order 25 -- 30 keV (FWHM). The complete E1 strength distribution from 5 to 20 MeV could be extracted from the data. The total E1 polarizability as well as the properties of the pygmy dipole resonance can be extracted with high precision providing important experimental constraints on the neutron skin thickness in 208Pb and the symmetry energy of neutron matter.

von Neumann-Cosel, P.; Poltoraska, I.; Tamii, A.

2013-03-01

82

Octupole deformation in sup 221 Fr; E1 transition rates  

SciTech Connect

Experimental data following the alpha decay of{sup 225}Ac are interpreted in terms of a spectroscopy in {sup 221}Fr consistent with octupole deformation. However, the measured E1 transition probabilities suggest that the low lying bands in {sup 221}Fr are considerably more mixed than in nuclei with slightly higher mass number. It is suggested that this mixing of states in {sup 221}Fr is indicative of the partial collapse of Nilsson-like orbitals into more degenerate shell model orbitals.

Liang, C.F.; Peghaire, A. (Centre de Spectrometrie Nucleaire et de Spectrometrie de Masse, Bat. 104-91406 Campus Orsay (FR)); Sheline, R.K. (Florida State Univ., Tallahassee, FL (USA))

1990-07-10

83

CESIUM OSCILLATOR STRENGTHS  

Microsoft Academic Search

Cesium oscillator strengths are calculated using oneelectron wave ; flunctions. These functions are numerical solutions of the Schrodinger equation ; with a central, symmetric potential and with the spin-orbit term. The potential ; is chosen so that the binding energies of the lowest ten levels agree with ; spectroscopic values to 3%; the next 30 levels agree to better than

Philip Stone

1962-01-01

84

Cesium Oscillator Strengths  

Microsoft Academic Search

Cesium oscillator strengths are calculated using one-electron wave functions. These functions are numerical solutions of the Schrödinger equation with a central, symmetric potential and with the spin-orbit term. The potential is chosen so that the binding energies of the lowest ten levels agree with spectroscopic values to 3%; the next 30 levels agree to better than 1%. The validity of

Philip M. Stone

1962-01-01

85

Strength of corundum concretes  

SciTech Connect

This article uses ultrasonic, acoustic emission, and mechanical procedures to comparatively test the strength properties of corundum-reinforced concrete refractories used in furnace liners in the face of thermal and corrosive factors with an eye toward enhancing their service life and reducing the heat and material losses in the furnaces which utilize them.

Usatikov, I.F.; Gal'chenko, T.G.; Karaulov, A.G.; Degtyareva, E.V.; Gogotsi, G.A.; Grushevskii, Ya.L.; Galenko, V.I.

1987-01-01

86

Preadolescent Strength Training.  

ERIC Educational Resources Information Center

Physical educators must teach preadolescents about safe and realistic strength-training methods commensurate with their needs and physical capabilities. The risk of injuries can be reduced by setting prudent goals, using equipment tailored to the age level, and educating students about their unique growth state. (PP)

Smith, Timothy K.

1984-01-01

87

Strength of Glueball Interactions.  

National Technical Information Service (NTIS)

The interaction strength between glueballs in a pure Yang-Mills theory is characterized by the triple glueball vertex function on-shell. This quantity is estimated by strong coupling methods. The result, which is in agreement with Monte Carlo calculations...

G. Muenster

1985-01-01

88

Gender Differences in Strength.  

ERIC Educational Resources Information Center

This investigation examined gender differences of 103 physically active men and women in upper and lower body strength as a function of lean body weight and the distribution of muscle and subcutaneous fat in the upper and lower limbs. Results are discussed. (Author/MT)

Heyward, Vivian H.; And Others

1986-01-01

89

Strength of Repaired Piles.  

National Technical Information Service (NTIS)

This report presents results from a two-year laboratory study to assess the strength of repaired pile sand to identify measures that would lead to improved efficiency. One third scale model pile specimens fabricated at a commercial prestressing facility w...

J. Fischer G. Mullins R. Sen

2000-01-01

90

Tensile Strength of Notched Composites  

Microsoft Academic Search

Two postulates on the strength of notched laminated composites are compared to experimental data. The first concerns the use of the fracture strength of angle ply composites to estimate the fracture strength of lami nates of several angle plys. The second concerns a macromechanics ex planation of the notch size effect on static strength for circular notches. The results of

Thomas A. Cruse

1973-01-01

91

17 CFR 274.127e-1 - Form N-27E-1, notice to periodic payment plan certificate holders of 18-month surrender rights...  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Form N-27E-1, notice to periodic payment plan certificate holders...to periodic payment plan certificates. 274.127e-1 Section 274.127e-1 Commodity and Securities Exchanges SECURITIES...

2013-04-01

92

Crossover Analysis of CHANG'E-1 Laser Altimeter Data  

NASA Astrophysics Data System (ADS)

This paper presents a preliminary result of crossover analysis and adjustment of Chang'E-1(CE-1) Laser Altimeter (LAM) data of the Moon for global and regional mapping applications. During the operation of Chang'E-1 from November 28, 2007 to December 4, 2008, the laser altimeter acquired 1400 orbital profiles with about 9.12 million altimetric points. In our experiment, we derived more than 1.38 million crossovers from 1395 ground tracks covering the entire lunar surface after eliminating outliers of orbits and altimetric points. A method of least-squares crossover adjustment with a series of basis functions of time (trigonometric functions and polynomials) is developed to reconcile the LAM data by minimizing the crossover residuals globally. The normal equations are very large but sparse; therefore they are stored and solved using sparse matrix technique. In a test area (0°N~60°N, 50°W~0°W), the crossover residuals are reduced from 62.1m to 32.8m, and the quality of the DEM generated from the adjusted LAM data is improved accordingly. We will optimize the method for the global adjustment to generate a high precision consistent global DEM, which can be used as absolute control for lunar mapping with orbital images.

Hu, W.; Yue, Z.; Di, K.

2011-08-01

93

Dipole strength functions in the actinide mass region  

SciTech Connect

We have calculated a number of neutron- and photon-induced reactions for the actinide nuclei /sup 232/Th, /sup 238/U, and /sup 237/Np. By fitting average resonance capture (ARC) measurements and total neutron capture data, we deduced absolute dipole strength functions for /sup 233/Th and /sup 239/U. We have found that the M1/E1 ratio is the same as in the /sup 176/Lu case, but the total transition strength was larger by about 27%. 17 refs., 4 figs., 1 tab.

Gardner, D.G.; Gardner, M.A.; Hoff, R.W.

1987-07-15

94

Reduction of benzene metabolism and toxicity in mice that lack CYP2E1 expression  

Microsoft Academic Search

Transgenic CYP2E1 knockout mice (cyp2e1-\\/-) were used toinvestigate the involvement of CYP2E1 in the in vivo metabolism of benzene and in the development of benzene-induced toxicity. After benzene exposure, absence of CYP2E1 protein was confirmed by Western blot analysis of mouse liver samples. For the metabolism studies, male cyp2e1-\\/- and wild-type control mice were exposed to 200 ppm benzene, along

John L. Valentine; Susanna S.-T. Lee; Mark J. Seaton; Bahman Asgharian; Georgia Farris; J. Christopher Corton; Frank J. Gonzalez; Michele A. Medinsky

1996-01-01

95

Tear Strength and Tensile Strength of Model Filled Elastomers.  

National Technical Information Service (NTIS)

Measurements have been made of the tear strength, tensile strength, and energy dissipated during stretching for model filled elastomers consisting of polybutadiene with glass beads incorporated. The glass beads were pretreated with various silanes, some o...

P. Dreyfuss A. N. Gent J. R. Williams

1980-01-01

96

Human adenovirus 2 E1B-19K and E1B-53K tumor antigens: antipeptide antibodies targeted to the NH2 and COOH termini.  

PubMed Central

The human adenovirus 2 (Ad2) transforming region is located in the left 11.1% of the viral genome and encodes two early transcription units, E1A and E1B. Based on the amino acid sequence deduced from the Ad2 E1B DNA sequence (Gingeras et al., J. Biol. Chem. 257:13475-13491, 1982), we have prepared antibodies against synthetic peptides, 8 to 16 amino acids in length, encoded at the NH2 and COOH termini of the major E1B-19K and E1B-53K tumor antigens. The antipeptide antibodies immunoprecipitated the targeted E1B-19K or E1B-53K tumor antigens from extracts of Ad2-infected cells. The specificity of the peptide competition studies. Antipeptide antibodies directed to the NH2 and COOH termini immunoprecipitated the E1B-19K and E1B-53K tumor antigens from two Ad2-transformed rat cell lines, F17 and F4, providing evidence that identical tumor antigens are synthesized in Ad2-infected and Ad2-transformed cells. These results show that the E1B-19K and E1B-53K T antigens are not processed proteolytically at either the NH2 or COOH terminus. Our data provide strong evidence at the protein level that the E1B-19K and E1B-53K tumor antigens partially overlap in DNA sequence, with the E1B-19K initiating translation at the first ATG at nucleotide 1711 in translation reading frame 1 and the E1B-53K tumor antigen initiating translation at the second ATG at nucleotide 2016 in reading frame 3. This confirms the results of others on the N-terminal amino acid sequence of E1B-19K and theoretical deductions based on the DNA sequence. Our findings prove that the large E1B-53K T antigen initiates translation at the second ATG at nucleotide 2016 and not at equally plausible initiation codons located farther downstream at nucleotides 2202 and 2235. Thus, the E1B-53K T antigen is another example of a protein which initiates translation at an internal ATG rather than at the 5'-proximal ATG. Images

Green, M; Brackmann, K H; Lucher, L A; Symington, J S; Kramer, T A

1983-01-01

97

Design shear strength formula for high strength concrete beams  

Microsoft Academic Search

After a brief review on the concrete shear strength mechanisms, two very reliable expressions for predicting the shear strength\\u000a of beams without transverse reinforcement are reported: the one proposed by Bažant and Kim [7], which is valid for Normal\\u000a strength Concrete (NSC) beams, and the other recently proposed by the authors, which is valid for High Strength Concrete (HSC)\\u000a beams.

G. Russo; G. Somma; P. Angeli

2004-01-01

98

E1A-mediated inhibition of myogenesis correlates with a direct physical interaction of E1A12S and basic helix-loop-helix proteins.  

PubMed Central

The observation that adenovirus E1A gene products can inhibit differentiation of skeletal myocytes suggested that E1A may interfere with the activity of myogenic basic helix-loop-helix (bHLH) transcription factors. We have examined the ability of E1A to mediate repression of the muscle-specific creatine kinase (MCK) gene. Both the E1A12S and E1A13S products repressed MCK transcription in a concentration-dependent fashion. In contrast, amino-terminal deletion mutants (d2-36 and d15-35) of E1A12S were defective for repression. E1A12S also repressed expression of a promoter containing a multimer of the MCK high-affinity E box (the consensus site for myogenic bHLH protein binding) that was dependent, in C3H10T1/2 cells, on coexpression of a myogenin bHLH-VP16 fusion protein. A series of coprecipitation experiments with glutathione S-transferase fusion and in vitro-translated proteins demonstrated that E1A12S, but not amino-terminal E1A deletion mutants, could bind to full-length myogenin and E12 and to deletion mutants of myogenin and E12 that spare the bHLH domains. Thus, the bHLH domains of myogenin and E12, and the high-affinity E box, are targets for E1A-mediated repression of the MCK enhancer, and domains of E1A required for repression of muscle-specific gene transcription also mediate binding to bHLH proteins. We conclude that E1A mediates repression of muscle-specific gene transcription through its amino-terminal domain and propose that this may involve a direct physical interaction between E1A and the bHLH region of myogenic determination proteins. Images

Taylor, D A; Kraus, V B; Schwarz, J J; Olson, E N; Kraus, W E

1993-01-01

99

Prepubescent Strength Training. Some Considerations.  

ERIC Educational Resources Information Center

Under the careful supervision of a trained fitness professional, the benefits of prepubescent strength training (improved strength, power, muscular endurance, bone density) outweigh the risks (acute and chronic musculoskeletal injuries). (CB)

Priest, Joe W.; Holshouser, Richard S.

1987-01-01

100

Failure Strength of Icy Lithospheres.  

National Technical Information Service (NTIS)

Lithospheric strengths derived from friction on pre-existing fractures and ductile flow laws show that the tensile strength of intact ice under applicable conditions is actually an order of magnitude stronger than widely assumed. It is demonstrated that t...

M. P. Golombek W. B. Banerdt

1987-01-01

101

Comparison between E1A gene from oncogenic and non-oncogenic adenoviruses in cellular transformation (Ad E1A conserved region).  

PubMed

All adenoviruses transform primary BRK cells in vitro, but only cells transformed by oncogenic adenoviruses are tumorigenic for immunocompetent animals. The transforming E1 regions of human Ad 2 and Ad 12 also differ from each other in the frequency in which they can transform BRK cells. We have investigated these properties which can be assigned to the specific domain of the E1A region. For this purpose, chimeric E1A regions between Ad 2 and Ad 12 have been constructed. The efficiency of cell transformation appeared to be determined by the encoding region. The promoter sequences were not important for an efficient cellular transformation although the E1B region cis activated in E1A transcription in both cell transformation and transient expression. We show that sequences located in the E1B promoter were responsible for this effect. In the encoding region the CR 1 domain was essential for the cell transformation frequency. PMID:8379854

Leclére, V; Huvent, I; Verwaerde, P; Cousin, C; D'Halluin, J C

1993-01-01

102

Cervical muscle strength after laminoplasty  

Microsoft Academic Search

.  ?To determine changes in cervical muscle strength after laminoplasty and to evaluate the relation between muscle strength\\u000a and neck pain, we measured maximum isometric muscle strength using a handheld dynamometer. We also investigated neck pain\\u000a before surgery and every month after surgery in 21 subjects who had undergone French-door laminoplasty. Muscle strength decreased\\u000a particularly 1 month after surgery, the extensor

Sueo Nakama; Kikuko Nitanai; Yoichi Oohashi; Teruaki Endo; Yuichi Hoshino

2003-01-01

103

Estrogen sulfotransferase/SULT1E1 promotes human adipogenesis.  

PubMed

Estrogen sulfotransferase (EST/SULT1E1) is known to catalyze the sulfoconjugation and deactivation of estrogens. The goal of this study is to determine whether and how EST plays a role in human adipogenesis. By using human primary adipose-derived stem cells (ASCs) and whole-fat tissues from the abdominal subcutaneous fat of obese and nonobese subjects, we showed that the expression of EST was low in preadipocytes but increased upon differentiation. Overexpression and knockdown of EST in ASCs promoted and inhibited differentiation, respectively. The proadipogenic activity of EST in humans was opposite to the antiadipogenic effect of the same enzyme in rodents. Mechanistically, EST promoted adipogenesis by deactivating estrogens. The proadipogenic effect of EST can be recapitulated by using an estrogen receptor (ER) antagonist or ER? knockdown. In contrast, activation of ER in ASCs inhibited adipogenesis by decreasing the recruitment of the adipogenic peroxisome proliferator-activated receptor ? (PPAR?) onto its target gene promoters, whereas ER antagonism increased the recruitment of PPAR? to its target gene promoters. Linear regression analysis revealed a positive correlation between the expression of EST and body mass index (BMI), as well as a negative correlation between ER? expression and BMI. We conclude that EST is a proadipogenic factor which may serve as a druggable target to inhibit the turnover and accumulation of adipocytes in obese patients. PMID:24567372

Ihunnah, Chibueze A; Wada, Taira; Philips, Brian J; Ravuri, Sudheer K; Gibbs, Robert B; Kirisci, Levent; Rubin, J Peter; Marra, Kacey G; Xie, Wen

2014-05-01

104

Strength Training for Young Athletes.  

ERIC Educational Resources Information Center

This guide is designed to serve as a resource for developing strength training programs for children. Chapter 1 uses research findings to explain why strength training is appropriate for children. Chapter 2 explains some of the important physiological concepts involved in children's growth and development as they apply to developing strength

Kraemer, William J.; Fleck, Steven J.

105

The strength of bilayered tablets  

Microsoft Academic Search

The tensile strength of model materials (dicalcium phosphate dihydrate, microcrystalline cellulose and pregelatinised starch) compacted to form tablets in the form of beams consisting of two layers of equal thickness has been determined by three-point loading. The values of the tensile strength of the materials were sometimes higher and sometimes lower than the tensile strength of beams of the same

F. Podczeck; K. R. Drake; J. M. Newton; I. Haririan

2006-01-01

106

Strength Training and Children's Health.  

ERIC Educational Resources Information Center

Provides an overview of the potential health benefits of strength training for children, discussing the role of strength training in preventing sports-related injuries and highlighting design considerations for such programs. The focus is on musculoskeletal adaptations to strength training that are observable in healthy children. Guidelines for…

Faigenbaum, Avery D.

2001-01-01

107

SHRINKAGE OF HIGH STRENGTH CONCRETE  

Microsoft Academic Search

This paper presents the results of an experimental investigation carried out to evaluate the shrinkage of High Strength Concrete. High Strength Concrete is made by partial replacement of cement by flyash and silica fume. The shrinkage of High Strength Concrete has been studied using the different types of coarse and fine aggregates i.e. Sandstone and Granite of 12.5 mm size

S. M. Gupta; P. Aggarwal; Y. Aggarwal

108

Strength of Rewelded Inconel 718  

NASA Technical Reports Server (NTRS)

Inconel 718, nickel-based alloy used extensively for high-temperature structural service, welded repeatedly without detriment to its strength. According to NASA report, tests show 12 repairs on same weld joint do not adversely affect ultimate tensile strenth, yield strength, fatigue strength, metallurgical grain structures, or ability of weld joint to respond to post weld heat treatments.

Bayless, E.; Lovoy, C. V.; Mcllwain, M. C.; Munafo, P.

1982-01-01

109

The Dual Effect of Adenovirus Type 5 E1A 13S Protein on NF-kB Activation Is Antagonized by E1B 19K  

Microsoft Academic Search

The genomes of human adenoviruses encode several regulatory proteins, including the two differentially spliced gene products E1A and E1B. Here, we show that the 13S but not the 12S splice variant of E1A of adenovirus type 5 can activate the human transcription factor NF-kB in a bimodal fashion. One mode is the activation of NF-kB containing the p65 subunit from

M. LIENHARD SCHMITZ; ALMUT INDORF; FLORIAN P. LIMBOURG; HEIKE STADTLER; E. BRITTA-MAREEN TRAENCKNER; ANDPATRICK A. BAEUERLE

1996-01-01

110

The dual effect of adenovirus type 5 E1A 13S protein on NF-kappaB activation is antagonized by E1B 19K.  

PubMed Central

The genomes of human adenoviruses encode several regulatory proteins, including the two differentially spliced gene products E1A and E1B. Here, we show that the 13S but not the 12S splice variant of E1A of adenovirus type 5 can activate the human transcription factor NF-kappaB in a bimodal fashion. One mode is the activation of NF-kappaB containing the p65 subunit from the cytoplasmic NF-kappaB-IkappaB complex. This activation required reactive oxygen intermediates and the phosphorylation of IkappaBalpha at serines 32 and 36, followed by IkappaBalpha degradation and the nuclear uptake of NF-kappaB. In addition, 13S E1A stimulated the transcriptional activity of the C-terminal 80 amino acids of p65 at a core promoter with either a TATA box or an initiator (INR) element. The C-terminal 80 amino acids of p65 were found to associate with E1A in vitro. The activation of NF-kappaB-dependent reporter gene transcription by E1A was potently suppressed upon coexpression of the E1B 19-kDa protein (19K). E1B 19K prevented both the activation of NF-kappaB and the E1A-mediated transcriptional enhancement of p65. These inhibitory effects were not found for the 55-kDa splice variant of the E1B protein. We suggest that the inductive effect of E1A 13S on the host factor NF-kappaB, whose activation is important for the transcription of various adenovirus genes, must be counteracted by the suppressive effect of E1B 19K so that the adenovirus-infected cell can escape the immune-stimulatory and apoptotic effects of NF-kappaB.

Schmitz, M L; Indorf, A; Limbourg, F P; Stadtler, H; Traenckner, E B; Baeuerle, P A

1996-01-01

111

Sequence-independent autoregulation of the adenovirus type 5 E1A transcription unit.  

PubMed Central

The adenovirus E1A gene is known to be autoregulated at the level of transcription. Autoregulation was found to be mediated by products of the E1A 13S mRNA, which induced a fivefold increase in E1A transcription rate. Deletion analysis suggested that the autoregulation did not require any specific sequence in the E1A transcriptional control region. This conclusion was reinforced by the demonstration that a cellular alpha-globin gene substituted for the E1A gene on the adenovirus chromosome was also positively regulated by E1A gene products. Images

Hearing, P; Shenk, T

1985-01-01

112

Improved Plant-based Production of E1 endoglucanase Using Potato: Expression Optimization and Tissue Targeting  

SciTech Connect

Optimization of Acidothermus cellulolyticus endoglucanase (E1) gene expression in transgenic potato (Solanum tuberosum L.) was examined in this study, where the E1 coding sequence was transcribed under control of a leaf specific promoter (tomato RbcS-3C) or the Mac promoter (a hybrid promoter of mannopine synthase promoter and cauliflower mosaic virus 35S promoter enhancer region). Average E1 activity in leaf extracts of potato transformants, in which E1 protein was targeted by a chloroplast signal peptide and an apoplast signal peptide were much higher than those by an E1 native signal peptide and a vacuole signal peptide. E1 protein accumulated up to 2.6% of total leaf soluble protein, where E1 gene was under control of the RbcS-3C promoter, alfalfa mosaic virus 5-untranslated leader, and RbcS-2A signal peptide. E1 protein production, based on average E1 activity and E1 protein accumulation in leaf extracts, is higher in potato than those measured previously in transgenic tobacco bearing the same transgene constructs. Comparisons of E1 activity, protein accumulation, and relative mRNA levels showed that E1 expression under control of tomato RbcS-3C promoter was specifically localized in leaf tissues, while E1 gene was expressed in both leaf and tuber tissues under control of Mac promoter. This suggests dual-crop applications in which potato vines serve as enzyme production `bioreactors' while tubers are preserved for culinary applications.

Dai, Ziyu; Hooker, Brian S.; Anderson, Daniel B.; Thomas, S R.

2000-06-01

113

A study of electron scattering from benzene: Excitation of the 1B1u, 3E2g, and 1E1u electronic states  

NASA Astrophysics Data System (ADS)

We report results from measurements for differential and integral cross sections of the unresolved 1B1u and 3E2g electronic states and the 1E1u electronic state in benzene. The energy range of this work was 10-200 eV, while the angular range of the differential cross sections was ~3°-130°. To the best of our knowledge there are no other corresponding theoretical or experimental data against which we can compare the present results. A generalized oscillator strength analysis was applied to our 100 and 200 eV differential cross section data, for both the 1B1u and 1E1u states, with optical oscillator strengths being derived in each case. The respective optical oscillator strengths were found to be consistent with many, but not all, of the earlier theoretical and experimental determinations. Finally, we present theoretical integral cross sections for both the 1B1u and 1E1u electronic states, as calculated within the BEf-scaling formalism, and compare them against relevant results from our measurements. From that comparison, an integral cross section for the optically forbidden 3E2g state is also derived.

Kato, Hidetoshi; Hoshino, Masamitsu; Tanaka, Hiroshi; Lima~O-Vieira, Paulo; Ingólfsson, Oddur; Campbell, Laurence; Brunger, Michael J.

2011-04-01

114

QM02 Strength Measurement  

SciTech Connect

In late April, Paul Emma reported that his orbit fitting program could find a reasonably good fit only if the strength of QM02 was changed from design value of -5.83 kG to -6.25 kG - a strength change of 7.3%. In late May, we made a focal length measurement of QM02 by turning off all focusing optics between YC07 and BPMS1 (in the spectrometer line) except for QM02 and adjusted the strength of QM02 so that vertical kicks by YC07 did not produce any displacements at BPMS1 (see Figure 1). The result was quoted in the LCLS elog was that QM02 appeared to 6% too weak, and approximately agreed with Paul's observation. The analysis used for the entry in the log book was based on the thin lens approximation and used the following numbers: Distance YC07 to QM02 - 5.128 m; Distance QM02 to BPMS1 - 1.778 m; and Energy - 135 MeV. These distances were computed from the X,Z coordinates given the on the large plot of the Injector on the wall of the control room. On review of the MAD output file coordinates, it seems that the distance used for QM02 to BPMS1 is not 1.778 m. The correct value is Distance, center of QM02 to BPMS1 - 1.845 m. There may be a typo on the wall chart values for the coordinates of BPMS1, or perhaps there was a misinterpretation of edge versus center of QM02. In any case, the effect of this change is that the thin lens estimate changes from 6% too weak to 9% too weak. At John Galayda's suggestion, we looked into the thin lens versus thick lens approximation. A Mathematica program was written to solve for the K value of the QM02, in the thick lens approximation, that provides point to point focusing from YC07 to BPMS1, and to compare this number with the value obtained using the thin lens approximation. The length of QM02 used in the thick lens calculation is the effective length determined by magnetic measurements of 0.108 m. The result of the Mathematica calculation is that the thin lens approximation predicts less magnet strength is required to produce the same focusing by about 1.3%. When both the distance correction and the thick lens approximation are taken into account, the result is: K{sub thick} - K{sub mm}/K{sub thick} = -7.6% where K{sub mm} is the value obtained from magnetic measurements and K{sub thick} is the value of K obtained from the focal length measurement in the thick lens approximation. That is, QM02 acts weaker than it was measured by magnetic measurements by 7.6%. This is remarkably close to Paul's original estimate. The unexpected weakness could in principle be due to several things: shorted turns, a current calibration error, magnetic measurement error; it could even be due to the presence of an gradient from QM01, which is of opposite sign and right next to QM02, despite it being set to zero current (although it was not DAC-zeroed). Plans have been implemented to remove and replace QM02 at the earliest ROD.

Welch, J; Wu, J.; /SLAC; ,

2010-11-24

115

Study of gamma-ray strength functions  

SciTech Connect

The use of gamma-ray strength function systematics to calculate neutron capture cross sections and capture gamma-ray spectra is discussed. The ratio of the average capture width, GAMMA/sub ..gamma../-bar, to the average level spacing, D/sub obs/, both at the neutron separation energy, can be derived from such systematics with much less uncertainty than from separate systematics for values of GAMMA/sub ..gamma../-bar and D/sub obs/. In particular, the E1 gamma-ray strength function is defined in terms of the giant dipole resonance (GDR). The GDR line shape is modeled with the usual Lorentzian function and also with a new energy-dependent, Breit-Wigner (EDBW) function. This latter form is further parameterized in terms of two overlapping resonances, even for nuclei where photonuclear measurements do not resolve two peaks. In the mass ranges studied, such modeling is successful for all nuclei away from the N = 50 closed neutron shell. Near the N = 50 shell, a one-peak EDBW appears to be more appropriate. Examples of calculated neutron capture excitation functions and capture gamma-ray spectra using the EDBW form are given for target nuclei in the mass-90 region and also in the Ta-Au mass region. 20 figures.

Gardner, D.G.; Gardner, M.A.; Dietrich, F.S.

1980-08-07

116

Polar mobilization of the Escherichia coli chromosome by the ColE1 transfer origin  

Microsoft Academic Search

Mobilization of the plasmid ColE1 from cells containing a conjugative plasmid (such as F) requires the synthesis of ColE1 mob proteins, and the presence, in cis, of bom (basis of mobility), a region of ColE1 containing the origin of transfer (oriT). The process of ColE1 transfer is thought to resemble that of the conjugative plasmid F, although the plasmids share

A. Christopher Boyd; David J. Sherratt

1986-01-01

117

Cytochrome P450 2E1 Genotype and the Susceptibility to Antituberculosis Drug-Induced Hepatitis  

Microsoft Academic Search

Most cases with antituberculosis drug-induced hepatitis have been attributed to isoniazid. Isoniazid is metabolized by hepatic N-acetyltransferase (NAT) and cytochrome P450 2E1 (CYP2E1) to form hepatotoxins. However, the role of CYP2E1 in this hepatotoxicity has not yet been reported. The aim of this study was to evaluate whether the polymorphism of the CYP2E1 gene is associated with antituberculosis drug-induced hepatitis.

Yi-Shin Huang; Herng-Der Chern; Wei-Juin Su; Jaw-Ching Wu; Shi-Chuan Chang; Chi-Huei Chiang; Full-Young Chang; Shou-Dong Lee

118

Cytochrome P450 2E1 genotype and the susceptibility to antituberculosis drug-induced hepatitis  

Microsoft Academic Search

Most cases with antituberculosis drug-induced hepatitis have been attributed to isoniazid. Isoniazid is metabolized by hepatic N-acetyltransferase (NAT) and cytochrome P450 2E1 (CYP2E1) to form hepatotoxins. However, the role of CYP2E1 in this hepatotoxicity has not yet been reported. The aim of this study was to evaluate whether the polymorphism of the CYP2E1 gene is associated with antituberculosis drug-induced hepatitis.

Yi-Shin Huang; Herng-Der Chern; Wei-Juin Su; Jaw-Ching Wu; Shi-Chuan Chang; Chi-Huei Chiang; Full-Young Chang; Shou-Dong Lee

2003-01-01

119

26 CFR 1.1402(e)-1A - Application of regulations under section 1402(e).  

Code of Federal Regulations, 2011 CFR

...Revenue 12 2011-04-01 2011-04-01 false Application of regulations under section 1402(e). 1.1402(e)-1A Section 1.1402(e)-1A Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED)...

2011-04-01

120

26 CFR 1.1402(e)-1A - Application of regulations under section 1402(e).  

Code of Federal Regulations, 2012 CFR

...Revenue 12 2012-04-01 2012-04-01 false Application of regulations under section 1402(e). 1.1402(e)-1A Section 1.1402(e)-1A Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED)...

2012-04-01

121

26 CFR 1.1402(e)-1A - Application of regulations under section 1402(e).  

...Revenue 12 2014-04-01 2014-04-01 false Application of regulations under section 1402(e). 1.1402(e)-1A Section 1.1402(e)-1A Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED)...

2014-04-01

122

26 CFR 1.1402(e)-1A - Application of regulations under section 1402(e).  

Code of Federal Regulations, 2010 CFR

...Revenue 12 2010-04-01 2010-04-01 false Application of regulations under section 1402(e). 1.1402(e)-1A Section 1.1402(e)-1A Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED)...

2010-04-01

123

26 CFR 1.1402(e)-1A - Application of regulations under section 1402(e).  

Code of Federal Regulations, 2013 CFR

...Revenue 12 2013-04-01 2013-04-01 false Application of regulations under section 1402(e). 1.1402(e)-1A Section 1.1402(e)-1A Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED)...

2013-04-01

124

Novel mechanism of JNK pathway activation by adenoviral E1A  

PubMed Central

The adenoviral oncoprotein E1A influences cellular regulation by interacting with a number of cellular proteins. In collaboration with complementary oncogenes, E1A fully transforms primary cells. As part of this action, E1A inhibits transcription of c-Jun:Fos target genes while promoting that of c-Jun:ATF2-dependent genes including jun. Both c-Jun and ATF2 are hyperphosphorylated in response to E1A. In the current study, E1A was fused with the ligand binding domain of the estrogen receptor (E1A-ER) to monitor the immediate effect of E1A activation. With this approach we now show that E1A activates c-Jun N-terminal kinase (JNK), the upstream kinases MKK4 and MKK7, as well as the small GTPase Rac1. Activation of the JNK pathway requires the N-terminal domain of E1A, and, importantly, is independent of transcription. In addition, it requires the presence of ERM proteins. Downregulation of signaling components upstream of JNK inhibits E1A-dependent JNK/c-Jun activation. Taking these findings together, we show that E1A activates the JNK/c-Jun signaling pathway upstream of Rac1 in a transcription-independent manner, demonstrating a novel mechanism of E1A action.

Morrison, Helen; Pospelova, Tatiana V.; Pospelov, Valery A.; Herrlich, Peter

2014-01-01

125

Novel mechanism of JNK pathway activation by adenoviral E1A.  

PubMed

The adenoviral oncoprotein E1A influences cellular regulation by interacting with a number of cellular proteins. In collaboration with complementary oncogenes, E1A fully transforms primary cells. As part of this action, E1A inhibits transcription of c-Jun:Fos target genes while promoting that of c-Jun:ATF2-dependent genes including jun. Both c-Jun and ATF2 are hyperphosphorylated in response to E1A. In the current study, E1A was fused with the ligand binding domain of the estrogen receptor (E1A-ER) to monitor the immediate effect of E1A activation. With this approach we now show that E1A activates c-Jun N-terminal kinase (JNK), the upstream kinases MKK4 and MKK7, as well as the small GTPase Rac1. Activation of the JNK pathway requires the N-terminal domain of E1A, and, importantly, is independent of transcription. In addition, it requires the presence of ERM proteins. Downregulation of signaling components upstream of JNK inhibits E1A-dependent JNK/c-Jun activation. Taking these findings together, we show that E1A activates the JNK/c-Jun signaling pathway upstream of Rac1 in a transcription-independent manner, demonstrating a novel mechanism of E1A action. PMID:24742962

Romanov, Vasily S; Brichkina, Anna I; Morrison, Helen; Pospelova, Tatiana V; Pospelov, Valery A; Herrlich, Peter

2014-04-30

126

Impact strength and indentation hardness of high-strength ceramics  

SciTech Connect

Hugoniot elastic limit and indentation hardness data are provided for selected high-strength ceramics AlN, Al{sub 2}O{sub 3}, B{sub 4}C, SiC, TiB, Zr{sub 2}. Degree of correlation of the strength data by the two test methods is examined. Influence of reformation mechanism on strength measurement, including rate sensitivity, size scale and confining pressure, is discussed.

Grady, D.E.

1993-08-01

127

Staphylococcal protein A as a fusion partner directs secretion of the e1alpha and e1beta subunits of pea mitochondrial pyruvate dehydrogenase by Bacillus subtilis.  

PubMed

Staphylococcal protein A (SPA)-based vectors were constructed to direct secretion of the E1alpha and E1beta subunits of Pisum sativum mitochondrial pyruvate dehydrogenase from Bacillus subtilis. These proteins were not exported when the signal peptide from levansucrase (SacBSP) was fused to their N-termini. Both SacBSP-E1alpha and SacBSP-E1beta fusion proteins were insoluble in the cytoplasm. However, when the SPA open-reading frame was inserted between SacBSP and E1alpha or E1beta, corresponding fusion proteins were secreted from the cells. The first (E) IgG-binding domain of SPA was sufficient to direct low level secretion of both fusion proteins (SacBSP-E-E1alpha and SacBSP-E-E1beta). Adding the second (D) IgG-binding domain improved extracellular protein yields 3- to 4-fold over E alone, but was not as efficient as secretion of the full-length (EDABC) SPA-fusion proteins. All constructs were based on the pUB110-derived multicopy plasmid pWB705. Separate B. subtilis strains transformed with SacBSP-E-E1alpha-His(6) or SacBSP-E1beta were cocultivated in the presence of Ni-NTA agarose. The native pyruvate dehydrogenase alpha2beta2 structure was bound to the affinity matrix, demonstrating assembly after secretion. The use of SPA as a fusion partner during expression of heterologous proteins by B. subtilis provides the basis of a versatile system that can be used to study both secretion and protein:protein interactions. PMID:10686156

Moreno, J I; Miernyk, J A; Randall, D D

2000-03-01

128

E1A induces phosphorylation of the retinoblastoma protein independently of direct physical association between the E1A and retinoblastoma products.  

PubMed Central

We have studied the initial effects of adenovirus E1A expression on the retinoblastoma (RB) gene product in normal quiescent cells. Although binding of the E1A products to pRB could, in theory, make pRB phosphorylation unnecessary for cell cycle progression, we have found that the 12S wild-type E1A product is capable of inducing phosphorylation of pRB in normal quiescent cells. The induction of pRB phosphorylation correlates with E1A-mediated induction of p34cdc2 expression and kinase activity, consistent with the possibility that p34cdc2 is a pRB kinase. Expression of simian virus 40 T antigen induces similar effects. Induction of pRB phosphorylation is independent of the pRB binding activity of the E1A products; E1A domain 2 mutants do not bind detectable levels of pRB but remain competent to induce pRB phosphorylation and to activate cdc2 protein kinase expression and activity. Although the kinetics of induction are slower, domain 2 mutants induce wild-type levels of pRB phosphorylation and host cell DNA synthesis and yet fail to induce cell proliferation. These results imply that direct physical interaction between the RB and E1A products does not play a required role in the early stages of E1A-mediated cell cycle induction and that pRB phosphorylation is not, of itself, sufficient to allow quiescent cells to divide. These results suggest that the E1A products do not need to bind pRB in order to stimulate resting cells to enter the cell cycle. Indeed, a more important role of the RB binding activity of the E1A products may be to prevent dividing cells from returning to G0. Images

Wang, H G; Draetta, G; Moran, E

1991-01-01

129

Resistance to Carbon Tetrachloride-Induced Hepatotoxicity in Mice Which Lack CYP2E1 Expression  

Microsoft Academic Search

CYP2E1 knockout mice (cyp2e1?\\/?) were used to investigate the involvement of CYP2E1 in the development of carbon tetrachloride (CCl4)-induced hepatotoxicity. Malecyp2e1?\\/?and wild-type (cyp2e1+\\/+) mice were given a single ip injection of 1 ml\\/kg (=1.59 g\\/kg) CCl4and 24 h later liver injury was assessed by elevations of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities and histopathology. No significant increases

Felice W.-Y. Wong; W.-Y. Chan; Susanna S.-T. Lee

1998-01-01

130

Resolvin E1 Metabolome in Local Inactivation during Inflammation-Resolution1  

Microsoft Academic Search

Resolvin E1 (RvE1; 5S,12R,18R-trihydroxy-6Z,8E,10E,14Z,16E-eicosapentaenoic acid) is a potent anti-inflammatory and prore- solving mediator derived from the omega-3 eicosapentaenoic acid. In this study, we report the RvE1 metabolome, namely, the metabolic products derived from RvE1. RvE1 was converted to several novel products by human polymorphonuclear leukocytes and whole blood as well as in murine inflammatory exudates, spleen, kidney, and liver. The

Song Hong; Timothy F. Porter; Yan Lu; Sungwhan F. Oh; Padmini S. Pillai; Charles N. Serhan

131

Strength of Chemical Bonds  

NASA Technical Reports Server (NTRS)

Students are not generally made aware of the extraordinary magnitude of the strengths of chemical bonds in terms of the forces required to pull them apart. Molecular bonds are usually considered in terms of the energies required to break them, and we are not astonished at the values encountered. For example, the Cl2 bond energy, 57.00 kcal/mole, amounts to only 9.46 x 10(sup -20) cal/molecule, a very small amount of energy, indeed, and impossible to measure directly. However, the forces involved in realizing the energy when breaking the bond operate over a very small distance, only 2.94 A, and, thus, f(sub ave) approx. equals De/(r - r(sub e)) must be very large. The forces involved in dissociating the molecule are discussed in the following. In consideration of average forces, the molecule shall be assumed arbitrarily to be dissociated when the atoms are far enough separated so that the potential, relative to that of the infinitely separated atoms, is reduced by 99.5% from the potential of the molecule at the equilibrium bond length (r(sub e)) for Cl2 of 1.988 A this occurs at 4.928 A.

Christian, Jerry D.

1973-01-01

132

Shrinkage of High Strength Concrete  

Microsoft Academic Search

? Abstract—This paper presents the results of an experimental investigation carried out to evaluate the shrinkage of High Strength Concrete. High Strength Concrete is made by partially replacement of cement by flyash and silica fume. The shrinkage of High Strength Concrete has been studied using the different types of coarse and fine aggregates i.e. Sandstone and Granite of 12.5 mm

S. M. Gupta; V. K. Sehgal; S. K. Kaushik

2009-01-01

133

Prolonged survival of adult rat pancreatic islets transfected with E1A-12S adenovirus.  

PubMed

It has been reported that various mutants of the E1A-adenovirus can activate quiescent differentiated cells to start proliferating. The aim of this study was to determine whether transfection with E1A-12S could extend the life span and functionality of pancreatic islets in culture. Rat pancreatic islets were isolated and transfected with retrovirus containing the adenovirus E1A-12S, E1A-13S, or control vectors. Transfection with the retroviral E1A-13S mutant produced extensive islet necrosis compared with nontransfected islets. Islets transfected with the control E1A mutant Ad5-dl312 vector (containing no E1A-12S or E1A-13S segments) were similar to nontransfected islets in their characteristics. We found that the E1A-12S transfected islets maintained greater viability, insulin granule structure, and glucose-induced insulin responsiveness over a 6-week period compared with mock or control islets. At 6 weeks of culture, the E1A-12S transfected islets also had fewer apoptotic cells compared with nontransfected islets. These data suggest that adenovirus E1A-12S can extend the functional life span of cultured rat pancreatic islets. PMID:10438166

Rutten, M J; Lester, L R; Quinlan, M P; Meshul, C K; Deveney, C W; Rabkin, J M

1999-08-01

134

Physiological Effects of Strength Training and Various Strength Training Devices.  

ERIC Educational Resources Information Center

Current knowledge in the area of muscle physiology is a basis for a discussion on strength training programs. It is now recognized that the expression of strength is related to, but not dependent upon, the size of the muscle and is probably more related to the ability to recruit more muscle fibers in the contraction, or to better synchronize their…

Wilmore, Jack H.

135

Strength properties of fly ash based controlled low strength materials  

Microsoft Academic Search

Controlled low strength material (CLSM) is a flowable mixture that can be used as a backfill material in place of compacted soils. Flowable fill requires no tamping or compaction to achieve its strength and typically has a load carrying capacity much higher than compacted soils, but it can still be excavated easily. The selection of CLSM type should be based

S. Türkel

2007-01-01

136

Role of E1B55K in E4orf6/E1B55K E3 Ligase Complexes Formed by Different Human Adenovirus Serotypes  

PubMed Central

The E4orf6 protein of serotypes representing all human adenovirus species forms Cullin-based E3 ubiquitin ligase complexes that facilitate virus infection by inducing degradation of cellular proteins that impede efficient viral replication. This complex also includes the viral E1B55K product believed to bind and introduce substrates for ubiquitination. Heterogeneity in the composition of these ligases exists, as some serotypes form Cul5-based complexes whereas others utilize Cul2. Significant variations in substrate specificities also exist among serotypes, as some degrade certain substrates very efficiently whereas others induce more modest or little degradation. As E1B55K is believed to function as the substrate acquisition component of the ligase, we undertook studies to compare the ability of representative E1B55K proteins to bind substrates with the efficacy of degradation by their respective E4orf6-based ligases. Interestingly, although efficient degradation in some cases corresponded to the ability of E1B55K to bind to or relocalize substrates, there were several examples of substrates that bound efficiently to E1B55K but were not degraded and others in which substrates were degraded even though binding to E1B55K was low or undetectable. These results suggest that transient interactions with E1B55K may be sufficient for efficient substrate degradation and that binding alone is not sufficient, implying that the orientation of the substrate in the ligase complex is probably crucial. Nevertheless, we found that the substrate specificity of certain E4orf6-based ligases could be altered through the formation of hybrid complexes containing E1B55K from another serotype, thus confirming identification of E1B55K as the substrate acquisition component of the complex.

Cheng, Chi Ying; Gilson, Timra; Wimmer, Peter; Schreiner, Sabrina; Ketner, Gary; Dobner, Thomas; Branton, Philip E.

2013-01-01

137

Electron Demagnetization and Collisionless Magnetic Reconnection in ?e ? 1 Plasmas: Theory and Observations  

NASA Astrophysics Data System (ADS)

Abrupt, intense bipolar and unipolar electric spikes with E > 100mV/m surveyed over 3 years of Polar data (Mozer et al 2005) have been organized to answer the limited question: can they be involved in the local demagnetization of thermal electrons? We determine a lower bound on the electric strength sufficient to cause non-gyrotropic effects on the electron pressure tensor of the form E>E*=B{we}/{8c Im}, where B is the ambient magnetic field strength, we=?2kTe/me, c is the speed of light, and Im is an electron velocity space weighted average displacement along the electric field while transiting the layer (assumed localized with a scale ? x=a ?e, where ?e is the electron thermal gyroradius). The variation of Im as a function of a for equal mean energy Maxwellian and more typical ? distributions seen in the Earth's magnetosphere provides strong evidence that the surveyed electric field spikes are generally smaller than E* (assuming ? 1), although 23% (n=57) exceed E* . Only 11% (n=6) of the bipolar class exceed E* ; the frequency of occurrence distribution for the bipolar class of spikes is peaked at 0.1E*. The unipolar occurrence is flat below E*, but has a significant 26% subgroup (n=51) that exceed E* . While E* does not depend on the ambient density, the occurrence distribution of all demagnetizing events is well organized by the ratio ?=?De/?e=&Omegace/?pe, residing almost exclusively in the regime ? <1. Spikes with E < E* generally occur with ? >1 . All the electrostatic spike events surveyed occur in the regime 10-8??e?3×10-2. The demagnetizing events of either class occupy the more restricted low beta regime 10-3??e?3×10-2. Because these demagnetizing events occur in ?e ? 1 they would not, however, be considered unmagnetized at current channels as thin as the electron skin depth, de, since for such current channels ?e ? ?e-1/2de ? de. As a group the subset of unipolar events with E > E* are consistently understood as sites where the electron pressure tensor could become deformed from cylindrical symmetry by electric field enhancement in layers with scale sizes up to the local thermal electron's gyroradius. Such a deformation is critical for a viable mechanism that supports collisionless reconnection. After selecting events as demagnetizing based on the size of the relevant forces and work done, the geophysical locale of their detection has been investigated. Previously, all E spikes in this survey were found near the invariant latitudes ? of the earth's magnetic cusps but at all magnetic local times. The demagnetizing events identified here via E* are strongly organized at magnetic local noon (with a secondary, much shallower maximum at local magnetic midnight), occur preferentially at orbit apogee, and without significant preference for the magnetic latitude of the spacecraft. These geophysical organizations are consistent with the demagnetizing E spikes as indices of ongoing, collisionless reconnection in low ?e regimes at the earth's subsolar magnetopause. The identification of this sub-class of electric spikes at low ?e with E>E* widens the observed venues in the E and B fields where topology changing departures from ideal MHD should be anticipated in collisionless astrophysical plasmas.

Scudder, J. D.; Mozer, F. S.

2005-05-01

138

Oscillator strengths and radiative rates for transitions in neutral sulfur  

SciTech Connect

We present accurate oscillator strengths and radiative rates for 2173 E1 transitions among the 120 levels belonging to 3s{sup 2}3p{sup 4}, 3s3p{sup 5}, and 3s{sup 2}3p{sup 3}({sup 4}S{sup o},{sup 2}D{sup o},{sup 2}P{sup o})nl configurations where nl=4s,5s,6s,4p,5p,6p,3d,4d,4f,5f. A configuration interaction approach is employed through the standard CIV3 program. The 114 LS states included in the present calculation generate 250 fine-structure levels belonging to the above configurations below 100,000 cm{sup -1}. However, results of only 120 fine-structure levels are presented due to the absence of experimental energy values for the remaining levels. Tabulations of oscillator strengths and radiative rates, and their comparison with other calculations, are presented in the first two tables. In a separate table the oscillator strengths and transition probabilities, in length and velocity gauges, are presented for 2173 E1 transitions, and are arranged in ascending order of wavelength.

Deb, N.C. [School of Mathematics and Physics, Queen's University Belfast, Belfast BT7 1NN, Northern Ireland (United Kingdom); Hibbert, A. [School of Mathematics and Physics, Queen's University Belfast, Belfast BT7 1NN, Northern Ireland (United Kingdom)], E-mail: a.hibbert@qub.ac.uk

2008-07-15

139

ELECTRON EXCITATION COLLISION STRENGTHS FOR SINGLY IONIZED NITROGEN  

SciTech Connect

Collision strengths for the astrophysically important lines in N II have been calculated in the close-coupling approximation using the B-spline Breit-Pauli R-matrix method. The multiconfiguration Hartree-Fock method with term-dependent non-orthogonal orbitals is employed for an accurate representation of the target wave functions. The close-coupling expansion includes 58 bound levels of N II. The 58 target levels belong to the terms of the ground 2s {sup 2}2p {sup 2} and singly excited 2s2p {sup 3}, 2s {sup 2}2p3s, 2s {sup 2}2p3p, 2s {sup 2}2p3d, 2s {sup 2}2p4s, 2s {sup 2}2p4p, and 2s2p {sup 2}3s configurations. The effective collision strengths are obtained by averaging the electron collision strengths over a Maxwellian distribution of velocities and these are tabulated for all 1653 fine-structure transitions among the 58 levels at electron temperatures in the range from 500 to 100,000 K. The line strengths, oscillator strengths, and transition probabilities for all E1 transitions are tabulated. The present results are compared with a variety of other close-coupling calculations. There is an overall good agreement with the 23-state calculation by Hudson and Bell in most part, but some significant differences are also noted for some transitions.

Tayal, S. S., E-mail: stayal@cau.edu [Department of Physics, Clark Atlanta University, Atlanta, GA 30314 (United States)

2011-08-01

140

Shear strength of granular materials  

Microsoft Academic Search

The shear strength properties of granular materials reflecttheir inherent force and fabric anisotropy. We analyze the role of fabric and force an isotropies with respect to the critical-state shear strength. Then, a model of accessiblegeometrical states in terms of particle connectivity and contact anisotropy is presented. This mod el incorporates in a simple way the fact that, due to steric

Farhang Radjai; Emilien Azéma

2009-01-01

141

Shear strength of granular materials  

Microsoft Academic Search

The shear strength properties of granular materials reflect their inherent force and fabric anisotropy. We analyze the role of fabric and force anisotropies with respect to the critical-state shear strength. Then, a model of accessible geometrical states in terms of particle connectivity and contact anisotropy is presented. This model incorporates in a simple way the fact that, due to steric

Farhang Radjai; Emilien Azéma

2009-01-01

142

Humor and strengths of character  

Microsoft Academic Search

Humor in the Values in Action (VIA) Classification of Strengths is conceptualized as a unipolar and unidimensional strength and is subsumed under the virtue of transcendence. Its scope is intentionally restricted to forms of humor that serve some moral good. The present study (N?=?203) investigated the relation between five dimensions of humorous conduct, sense of humor, and the VIA-Inventory of

Liliane Müller; Willibald Ruch

2011-01-01

143

Shear Strength of Wood Beams  

Microsoft Academic Search

Experimental shear strength research conducted cooperatively with the USDA Forest Service, Forest Products Laboratory; Washington State University; and the Federal Highway Administration on solid-sawn beams is summarized in this paper. Douglas Fir, Engelmann Spruce, and Southern Pine specimens were tested in a green condition to determine shear strength in members without checks and splits. Sizes tested ranged from nominal 51

Douglas R. Rammer; David I. McLean

144

The target strengths of fish  

Microsoft Academic Search

Knowledge of the acoustic target strength of a fish (or of a shoal of fish) is required to enable the performance of present and future sonar equipments to be determined for fish targets. Also, it is hoped that measurement of the strengths and characters of the echoes received from fish will give a reliable guide to the size of the

R. W. G. Haslett

1969-01-01

145

The Anti-Tumor Activity of E1A and its Implications in Cancer Therapy.  

PubMed

The adenovirus type 5 E1A protein (E1A) plays a critical role in anti-cancer gene therapy and has been tested in clinical trials. The expression of E1A significantly reduces tumorigenesis, promotes cell death, and inhibits cancer cell mobility. Chemosensitization is one of the anti-tumor effects of E1A, increasing in vitro and in vivo sensitization of anti-cancer drugs, including cisplatin, gemcitabine, etoposide, doxorubicin, paclitaxel, and tumor necrosis factor-related apoptosis-inducing ligand and histone deacetylase inhibitors in different types of cancer cells. E1A also demonstrates anti-metastasis activity through various molecular mechanisms such as the repression of protease expression, suppression of HER2/neu and downregulation of microRNA (miR-520h). Moreover, E1A has been reported to reprogram transcription in tumor cells and stabilize tumor suppressors such as PP2A/C, p21 and p53. Because E1A plays a potentially significant role in anti-tumor therapy, there exists an urgent need to study the anti-cancer activities of E1A. This paper presents a review of our current understanding of the tumor-suppressive functions and molecular regulation of E1A, as well as the potential clinical applications of E1A. PMID:24504082

Chang, Yi-Wen; Hung, Mien-Chie; Su, Jen-Liang

2014-06-01

146

Hydrate adhesive and tensile strengths  

NASA Astrophysics Data System (ADS)

The physical properties of hydrate-bearing sediments depend on the interaction between hydrates and minerals. In particular, hydrates prefer to nucleate on mineral surfaces, therefore, the hydrate-mineral adhesive strength and the tensile strength of the hydrate mass itself affect the mechanical response of hydrate-bearing sediments. In this study, ice and hydrates made with various guest molecules (CO2, CH4, and THF) are formed between mica and calcite substrates. Adhesive and tensile strengths are measured by applying an external pull-out force. Results show that tensile failure occurs in CO2 and CH4 hydrates when calcite is the substrate, while ice and all hydrates exhibit adhesive failure on mica. The debonding strength is higher when calcite substrates are involved rather than mica substrates. A nominal pull-out strength of 0.15 ± 0.03 MPa can be adopted for mechanical analyses of hydrate-bearing sediments.

Jung, J. W.; Santamarina, J. Carlos

2011-08-01

147

Strength properties of fly ash based controlled low strength materials.  

PubMed

Controlled low strength material (CLSM) is a flowable mixture that can be used as a backfill material in place of compacted soils. Flowable fill requires no tamping or compaction to achieve its strength and typically has a load carrying capacity much higher than compacted soils, but it can still be excavated easily. The selection of CLSM type should be based on technical and economical considerations for specific applications. In this study, a mixture of high volume fly ash (FA), crushed limestone powder (filler) and a low percentage of pozzolana cement have been tried in different compositions. The amount of pozzolana cement was kept constant for all mixes as, 5% of fly ash weight. The amount of mixing water was chosen in order to provide optimum pumpability by determining the spreading ratio of CLSM mixtures using flow table method. The shear strength of the material is a measure of the materials ability to support imposed stresses on the material. The shear strength properties of CLSM mixtures have been investigated by a series of laboratory tests. The direct shear test procedure was applied for determining the strength parameters Phi (angle of shearing resistance) and C(h) (cohesion intercept) of the material. The test results indicated that CLSM mixtures have superior shear strength properties compared to compacted soils. Shear strength, cohesion intercept and angle of shearing resistance values of CLSM mixtures exceeded conventional soil materials' similar properties at 7 days. These parameters proved that CLSM mixtures are suitable materials for backfill applications. PMID:17331642

Türkel, S

2007-08-25

148

Photoneutron cross sections for 118--124Sn and the ?-ray strength function method  

NASA Astrophysics Data System (ADS)

Photoneutron cross sections were measured for 118Sn, 119Sn, 120Sn, 122Sn, and 124Sn near neutron threshold with quasi-monochromatic laser-Compton scattering ? rays. A systematic analysis of the present photoneutron data and existing neutron-capture data is made using the ?-ray strength function on the basis of the HFB + QRPA model of E1 strength supplemented with a pygmy dipole resonance, which was deduced from a previous study on 116Sn and 117Sn. Radiative neutron capture cross sections for two radioactive nuclei, 121Sn and 123Sn, are deduced through the ?-ray strength function method.

Utsunomiya, H.; Goriely, S.; Kamata, M.; Akimune, H.; Kondo, T.; Itoh, O.; Iwamoto, C.; Yamagata, T.; Toyokawa, H.; Lui, Y.-W.; Harada, H.; Kitatani, F.; Goko, S.; Hilaire, S.; Koning, A. J.

2011-11-01

149

Induction by adenovirus-5 E1A of the differentiation phenotype of F9 teratocarcinoma cells involves a conserved region (CR1) of E1A.  

PubMed

The effects of the E1A protein of adenovirus-5 on the differentiation program of F9 teratocarcinoma cells were examined by the stable introduction of plasmids that expressed wild-type or mutated forms of E1A. Constitutive expression of plasmids for most of the mutant E1As induced loss of expression of the cell-surface antigen SSEA-1 and the enhanced expression of genes specific for the differentiated phenotype of F9 cells, such as genes for laminin B1, tissue-type plasminogen activator (tPA) and type IV collagen, as well as the altered cell morphology that is associated with the differentiated state. However, such changes were not observed in the case of genes for mutant proteins from which a conserved region (CR1) of E1A had been deleted. Furthermore, no significant induction of expression of the c-jun gene or transactivation of the c-jun-CAT reporter gene were observed when the sequence that encodes CR1 of E1A had been deleted. A palindromic sequence element (DRE) of the c-jun promoter was essential for the E1A-mediated up-regulation of the c-jun gene. These results imply that CR1 is required for activation of the c-jun gene and that it is implicated in the growth arrest, expression of parietal endoderm-specific functions and the orderly differentiation of F9 cells. PMID:7742380

Li, H O; Tang, X; Kitabayashi, I; Gachelin, G; Chiu, R; Yokoyama, K

1995-04-28

150

Distinct and redundant functions of cyclin E1 and cyclin E2 in development and cancer  

Microsoft Academic Search

The highly conserved E-type cyclins are core components of the cell cycle machinery, facilitating the transition into S phase through activation of the cyclin dependent kinases, and assembly of pre-replication complexes on DNA. Cyclin E1 and cyclin E2 are assumed to be functionally redundant, as cyclin E1-\\/- E2-\\/- mice are embryonic lethal while cyclin E1-\\/- and E2-\\/- single knockout mice

C ELIZABETH Caldon; Elizabeth A Musgrove

2010-01-01

151

Largazole and Its Derivatives Selectively Inhibit Ubiquitin Activating Enzyme (E1)  

PubMed Central

Protein ubiquitination plays an important role in the regulation of almost every aspect of eukaryotic cellular function; therefore, its destabilization is often observed in most human diseases and cancers. Consequently, developing inhibitors of the ubiquitination system for the treatment of cancer has been a recent area of interest. Currently, only a few classes of compounds have been discovered to inhibit the ubiquitin-activating enzyme (E1) and only one class is relatively selective in E1 inhibition in cells. We now report that Largazole and its ester and ketone analogs selectively inhibit ubiquitin conjugation to p27Kip1 and TRF1 in vitro. The inhibitory activity of these small molecules on ubiquitin conjugation has been traced to their inhibition of the ubiquitin E1 enzyme. To further dissect the mechanism of E1 inhibition, we analyzed the effects of these inhibitors on each of the two steps of E1 activation. We show that Largazole and its derivatives specifically inhibit the adenylation step of the E1 reaction while having no effect on thioester bond formation between ubiquitin and E1. E1 inhibition appears to be specific to human E1 as Largazole ketone fails to inhibit the activation of Uba1p, a homolog of E1 in Schizosaccharomyces pombe. Moreover, Largazole analogs do not significantly inhibit SUMO E1. Thus, Largazole and select analogs are a novel class of ubiquitin E1 inhibitors and valuable tools for studying ubiquitination in vitro. This class of compounds could be further developed and potentially be a useful tool in cells.

Nasveschuk, Christopher G.; Wang, Wei; Quade, Bettina; Zhang, Gan; Kuchta, Robert D.; Phillips, Andrew J.; Liu, Xuedong

2012-01-01

152

Trisomic analysis of a strong photoperiod-sensitivity gene E1 in rice (Oryza sativa L.)  

Microsoft Academic Search

Recent genetic analyses on heading-time of rice indicated that almost all the well-adapted varieties in the temperate zone\\u000a carry a strong photoperiod-sensitivity gene E1, a dominant allele of E1 locus. In order to identify the chromosome on which\\u000a E1 is located, a trisomic analysis was made using two primary trisomic series originating from the japonica varieties, Nipponbare\\u000a and Kinmaze, respectively.

Yutaka Okumoto; Takatoshi Tanisaka

1997-01-01

153

Identification of the catalytic glutamate in the E1 component of human pyruvate dehydrogenase  

Microsoft Academic Search

The pyruvate dehydrogenase complex catalyzes the conversion of pyruvate to acetyl-CoA. The first component (E1) converts pyruvate to bound acetaldehyde using thiamine diphosphate (ThDP) and Mg2+ as cofactors. There is no 3D structure of E1 available but those of other ThDP-dependent enzymes show some similarities including a glutamate residue that assists in ThDP activation. Eukaryotic E1 has an ?2?2 structure

Rui Fang; Peter F. Nixon; Ronald G. Duggleby

1998-01-01

154

Glycoprotein E1 of hog cholera virus expressed in insect cells protects swine from hog cholera.  

PubMed

The processing and protective capacity of E1, an envelope glycoprotein of hog cholera virus (HCV), were investigated after expression of different versions of the protein in insect cells by using a baculovirus vector. Recombinant virus BacE1[+] expressed E1, including its C-terminal transmembrane region (TMR), and generated a protein which was similar in size (51 to 54 kDa) to the size of E1 expressed in swine kidney cells infected with HCV. The protein was not secreted from the insect cells, and like wild-type E1, it remained sensitive to endo-beta-N-acetyl-D-glucosaminidase H (endo H). This indicates that E1 with a TMR accumulates in the endoplasmic reticulum or cis-Golgi region of the cell. In contrast, recombinant virus BacE1[-], which expressed E1 without a C-terminal TMR, generated a protein that was secreted from the cells. The fraction of this protein that was found to be cell associated had a slightly lower molecular mass (49 to 52 kDa) than wild-type E1 and remained endo H sensitive. The high-mannose units of the secreted protein were trimmed during transport through the exocytotic pathway to endo H-resistant glycans, resulting in a protein with a lower molecular mass (46 to 48 kDa). Secreted E1 accumulated in the medium to about 30 micrograms/10(6) cells. This amount was about 3-fold higher than that of cell-associated E1 in BacE1[-] and 10-fold higher than that of cell-associated E1 in BacE1[+]-infected Sf21 cells. Intramuscular vaccination of pigs with immunoaffinity-purified E1 in a double water-oil emulsion elicited high titers of neutralizing antibodies between 2 and 4 weeks after vaccination at the lowest dose tested (20 micrograms). The vaccinated pigs were completely protected against intranasal challenge with 100 50% lethal doses of HCV strain Brescia, indicating that E1 expressed in insect cells is an excellent candidate for development of a new, safe, and effective HCV subunit vaccine. PMID:8350404

Hulst, M M; Westra, D F; Wensvoort, G; Moormann, R J

1993-09-01

155

Adenovirus type 5 E1A-induced apoptosis in COX-2-overexpressing breast cancer cells  

PubMed Central

Introduction Suppression of Bcl-2 expression can overcome cellular resistance to apoptosis induced by the adenovirus type 5 gene E1A in models of ovarian and breast cancer. Celecoxib, a cyclooxygenase-2 (COX-2) inhibitor, is known to downregulate Bcl-2 expression. We hypothesized that celecoxib would enhance E1A-induced apoptosis by suppressing Bcl-2 through suppressing COX-2 expression. If successful, this strategy could represent a means of overcoming resistance to E1A gene therapy. Methods We first established the cytotoxicity of celecoxib in two COX-2-overexpressing E1A-transfected breast cancer cell lines (MDA-MB-231 and MDA-MB-435) and in two low-COX-2-expressing E1A-transfected cell lines (MCF-7 (breast cancer) and SKOV3.ip1 (ovarian cancer)). We next tested whether higher sensitivity to celecoxib among these cell lines resulted from increased apoptosis by flow cytometry and western blotting. We further investigated whether suppression of Bcl-2 by celecoxib was involved in the apoptosis resulting from celecoxib treatment, and we explored whether the celecoxib-induced apoptosis in these cells depends on a COX-2 downstream pathway. Results The two COX-2-overexpressing cell lines MDA-MB-231-E1A and MDA-MB-435-E1A were more sensitive to celecoxib than the corresponding control cells, but the two low-COX-2-expressing cell lines MCF-7-E1A and SKOV3.ip1-E1A were no more sensitive than control cells to celecoxib. Therefore, we used the MDA-MB-231-E1A and MDA-MB-435-E1A cells for all further experiments. In both cell lines, sub-G1 fraction was increased, or cleavage of PARP and caspase-9 were increased after 5 days of exposure to 40 ?M celecoxib. However, Bcl-2 was suppressed only in the MDA-MB-435-E1A cells and not in the MDA-MB-231-E1A cells. Restoring Bcl-2 expression in the MDA-MB-435-E1A stable transfectants did not affect their sensitivity to celecoxib. However, adding prostaglandin E2 (PGE2) or PGF2? blunted the sensitivity to celecoxib of both E1A stable transfectants. Conclusion We speculate that one mechanism by which celecoxib enhances E1A-induced apoptosis in cells that express high levels of COX-2 is through blocking PGE2 or PGF2?.

Sugimoto, Takeshi; Bartholomeusz, Chandra; Tari, Ana M; Ueno, Naoto T

2007-01-01

156

Papillomavirus E1 Protein Binds to and Stimulates Human Topoisomerase I  

PubMed Central

The papillomavirus (PV) E1 helicase plays a direct role in recruiting cellular DNA replication factors, such as replication protein A or polymerase ?-primase, to replicate PV genomes. Here, E1 is shown to bind to human topoisomerase I and stimulate its relaxation activity up to sevenfold. The interaction between E1 and topoisomerase I was mapped to the E1 DNA binding domain and C terminus. These findings imply a mechanism for the recruitment of topoisomerase I to PV DNA replication forks and for stimulating topoisomerase I to allow for efficient relaxation of the torsional stress induced by replication fork progression.

Clower, Randolph V.; Fisk, John C.; Melendy, Thomas

2006-01-01

157

Oscillator strengths and lifetimes of Zn I and Ga II  

NASA Astrophysics Data System (ADS)

We have applied the second-order relativistic many-body perturbation theory to calculate the oscillator strengths for the spin-allowed electric-dipole (E1) transitions in Zn I and Ga II. We have studied 11 transitions among the first 12 levels of Zn I and Ga II. Radiative lifetimes of some levels in Zn I and Ga II are also evaluated. In particular, the present study provides the first relativistic calculation for the transitions (4s4p)\\ ^{3}P_{0,1,2}^{o}\\rightarrow (4p^{2})\\ ^{3}P_{0,1,2} in Zn I whose oscillator strengths are sensitive to the interplay between the relativistic effects and the bound-continuum correlations. The transition amplitudes obtained in different gauges agree within 2%. The present results agree well with experiment.

Chi, Hsin-Chang; Chou, Hsiang-Shun

2014-03-01

158

Adenovirus E1A Oncogene Induces Rereplication of Cellular DNA and Alters DNA Replication Dynamics  

PubMed Central

The oncogenic property of the adenovirus (Ad) transforming E1A protein is linked to its capacity to induce cellular DNA synthesis which occurs as a result of its interaction with several host proteins, including pRb and p300/CBP. While the proteins that contribute to the forced induction of cellular DNA synthesis have been intensively studied, the nature of the cellular DNA replication that is induced by E1A in quiescent cells is not well understood. Here we show that E1A expression in quiescent cells leads to massive cellular DNA rereplication in late S phase. Using a single-molecule DNA fiber assay, we studied the cellular DNA replication dynamics in E1A-expressing cells. Our studies show that the DNA replication pattern is dramatically altered in E1A-expressing cells, with increased replicon length, fork velocity, and interorigin distance. The interorigin distance increased by about 3-fold, suggesting that fewer DNA replication origins are used in E1A-expressing cells. These aberrant replication events led to replication stress, as evidenced by the activation of the DNA damage response. In earlier studies, we showed that E1A induces c-Myc as a result of E1A binding to p300. Using an antisense c-Myc to block c-Myc expression, our results indicate that induction of c-Myc in E1A-expressing cells contributes to the induction of host DNA replication. Together, our results suggest that the E1A oncogene-induced cellular DNA replication stress is due to dramatically altered cellular replication events and that E1A-induced c-Myc may contribute to these events.

Singhal, Ghata; Leo, Elisabetta; Setty, Saayi Krushna Gadham; Pommier, Yves

2013-01-01

159

Adenovirus E1A oncogene induces rereplication of cellular DNA and alters DNA replication dynamics.  

PubMed

The oncogenic property of the adenovirus (Ad) transforming E1A protein is linked to its capacity to induce cellular DNA synthesis which occurs as a result of its interaction with several host proteins, including pRb and p300/CBP. While the proteins that contribute to the forced induction of cellular DNA synthesis have been intensively studied, the nature of the cellular DNA replication that is induced by E1A in quiescent cells is not well understood. Here we show that E1A expression in quiescent cells leads to massive cellular DNA rereplication in late S phase. Using a single-molecule DNA fiber assay, we studied the cellular DNA replication dynamics in E1A-expressing cells. Our studies show that the DNA replication pattern is dramatically altered in E1A-expressing cells, with increased replicon length, fork velocity, and interorigin distance. The interorigin distance increased by about 3-fold, suggesting that fewer DNA replication origins are used in E1A-expressing cells. These aberrant replication events led to replication stress, as evidenced by the activation of the DNA damage response. In earlier studies, we showed that E1A induces c-Myc as a result of E1A binding to p300. Using an antisense c-Myc to block c-Myc expression, our results indicate that induction of c-Myc in E1A-expressing cells contributes to the induction of host DNA replication. Together, our results suggest that the E1A oncogene-induced cellular DNA replication stress is due to dramatically altered cellular replication events and that E1A-induced c-Myc may contribute to these events. PMID:23740993

Singhal, Ghata; Leo, Elisabetta; Setty, Saayi Krushna Gadham; Pommier, Yves; Thimmapaya, Bayar

2013-08-01

160

Strength and Microstructure of Ceramics.  

National Technical Information Service (NTIS)

Our goal in this program continues to be the understanding of the role of microstructure in the strength properties of ceramics. It is becoming increasingly apparent to the brittle fracture community that the toughness characteristics and flaw distributio...

B. R. Lawn P. L. Swanson C. J. Fairbanks B. J. Hockey Y. W. Mai

1987-01-01

161

High Strength Steel Weldment Reliability.  

National Technical Information Service (NTIS)

The development of methods to control the diffusible hydrogen content during high strength steel welding was performed. The perfection of the use of irreversible weld metal hydrogen traps was demonstrated. Efforts have effectively alleviated the available...

D. L. Olson

2001-01-01

162

Information content of the low-energy electric dipole strength: Correlation analysis  

NASA Astrophysics Data System (ADS)

Background: Recent experiments on the electric dipole (E1) polarizability in heavy nuclei have stimulated theoretical interest in the low-energy electric dipole strength, both isovector and isoscalar.Purpose: We study the information content carried by the electric dipole strength with respect to isovector and isoscalar indicators characterizing bulk nuclear matter and finite nuclei. To separate isoscalar and isovector modes, and low-energy strength and giant resonances, we analyze the E1 strength as a function of the excitation energy E and momentum transfer q.Methods: We use the self-consistent nuclear density functional theory with Skyrme energy density functionals, augmented by the random phase approximation, to compute the E1 strength and covariance analysis to assess correlations between observables. Calculations are performed for the spherical, doubly magic nuclei 208Pb and 132Sn.Results: We demonstrate that E1 transition densities in the low-energy region below the giant dipole resonance exhibit appreciable state dependence and multinodal structures, which are fingerprints of weak collectivity. The correlation between the accumulated low-energy strength and the symmetry energy is weak, and dramatically depends on the energy cutoff assumed. On the other hand, a strong correlation is predicted between isovector indicators and the accumulated isovector strength at E around 20 MeV and momentum transfer q˜0.65 fm-1.Conclusions: Momentum- and coordinate-space patterns of the low-energy dipole modes indicate a strong fragmentation into individual particle-hole excitations. The global measure of low-energy dipole strength correlates poorly with the nuclear symmetry energy and other isovector characteristics. Consequently, our results do not support the suggestion that there exists a collective “pygmy dipole resonance,” which is a strong indicator of nuclear isovector properties. By considering nonzero values of momentum transfer, one can isolate individual excitations and nicely separate low-energy excitations from the T=1 and T=0 giant collective modes. That is, measurements at q>0 may serve as a tool to correlate the E1 strength with certain bulk observables, such as incompressibility and symmetry energy.

Reinhard, P.-G.; Nazarewicz, W.

2013-01-01

163

Temperature Dependence of the AlN E1(To) Phonon Decay, Thermal Expansion and Strain Effect in AlN/Sapphire by Infrared Reflection  

NASA Astrophysics Data System (ADS)

Infrared reflectivity measurement is carried out for AlN films on sapphire substrates. The frequencies of the symmetry optical phonon E1(TO) in the temperature range from 77 K to 500 K are reported by fitting the experimental reflectivity with the classical multi-oscillators model. Taking the lattice thermal expansion and Klemens process of the phonon decay into account, along with the strain effect introduced by thermal mismatch between the film and the substrate, the temperature effect on the frequency of the optical phonon E1(TO) is revealed. It is shown that the shift of frequency is mainly attributed to the decay process while the strain effect induced by thermal mismatch plays a non-negligible role in the outcomes of the strength and damping parameters.

Zhou, Shu-Tong; Yu, Chen-Hui; Zhang, Bo

2013-09-01

164

Strengths of Aboriginal Foster Parents  

Microsoft Academic Search

The purpose of the study was to identify the strengths of Aboriginal foster parents according to the foster parents themselves.\\u000a A total of 83 Aboriginal foster parents participated in over the phone interviews that included the question “What are the\\u000a main strengths you have as a foster parent?”. Responses to the questions were sorted by the participants and the sorted

Viktoria Ivanova; Jason Brown

2011-01-01

165

Fluid Overpressures and Crustal Strength  

NASA Astrophysics Data System (ADS)

The classic crustal strength-depth profile, based on experimental rock mechanics, predicts a brittle strength (?1 - ?3) = ?(¯? gz - Pf) that increases linearly with depth z, which is a consequence of [1] the intrinsic pressure dependence ? of brittle frictional strength plus [2] an assumption that pore-fluid pressure is hydrostatic, Pf = ?wgz. Much deep borehole stress data agree with a critical state of failure of this form. In contrast, fluid pressures greater than hydrostatic ?¯ gz > Pf > ?wgz are normally observed in deeper parts of thick clastic sedimentary basins on continental margins and active shale-rich plate-boundary mountain belts. We explore the predicted shape of the crustal strength-depth profile in such overpressured regions, particularly those dominated by the widespread disequilibrium compaction mechanism, which displays fully compacted sediments with hydrostatic fluid pressures at shallow depths until the fluid-retention depth zFRD is reached, below which sediments are increasingly undercompacted for their depth and overpressured. We show that the brittle strength at depths greater than zFRD is predicted to be approximately constant, leading to a crustal strength profile that is radically different from the classic linearly increasing hydrostatic profile. We present borehole stress and fluid-pressure measurements in several overpressured deforming continental margins that agree with this prediction and with a critical state of failure controlled by the same pressure-dependence ? as the overlying hydrostatic strata. A first-order extrapolation of observed and theoretical overpressured strength-depth profiles to much greater depths suggests the possibility of a prolonged transition at approximately constant strength from brittle to linear-viscous behavior in deforming shale-rich volumes undergoing the transition to slate, phyllite and schist. Our examples of fluid pressures and stresses come from the Yinggehai basin offshore south China, western Taiwan thrust belt, offshore Texas, Brunei delta and Scotia Shelf offshore Canada.

Suppe, John

2010-05-01

166

40 CFR Figure E-1 to Subpart E of... - Designation Testing Checklist  

Code of Federal Regulations, 2013 CFR

...Physical (Design) and Performance Characteristics of Reference Methods and Class I and Class II Equivalent Methods for PM 2.5 or PM 10-2,5 Pt. 53, Subpt. E, Fig. E-1 Figure E-1 to Subpart E of Part 53âDesignation Testing...

2013-07-01

167

77 FR 42677 - Special Conditions: General Electric CT7-2E1 Turboshaft Engine  

Federal Register 2010, 2011, 2012, 2013

...for an amendment to type certificate E8NE...CT7-2E1 turboshaft engine model. The CT7-2E1...derivative of the CT7 engine family certified...is a free turbine turbo shaft designed for...transport category twin-engine helicopter. The...design feature. Type Certification...

2012-07-20

168

Stereochemical assignment, antiinflammatory properties, and receptor for the omega-3 lipid mediator resolvin E1  

Microsoft Academic Search

The essential fatty acid eicosapentaenoic acid (EPA) present in fish oils displays beneficial effects in a range of human disorders associated with inflammation including cardiovascular disease. Resolvin E1 (RvE1), a new bioactive oxygenated product of EPA, was identified in human plasma and prepared by total organic synthesis. Results of bioaction and physical matching studies indicate that the complete structure of

Makoto Arita; Francesca Bianchini; Julio Aliberti; Alan Sher; Nan Chiang; Song Hong; Rong Yang; Nicos A. Petasis; Charles N. Serhan

169

CK2 Phosphorylation Inactivates DNA Binding by the Papillomavirus E1 and E2 Proteins  

PubMed Central

Papillomaviruses have complex life cycles that are understood only superficially. Although it is well established that the viral E1 and E2 proteins play key roles in controlling viral transcription and DNA replication, how these factors are regulated is not well understood. Here, we demonstrate that phosphorylation by the protein kinase CK2 controls the biochemical activities of the bovine papillomavirus E1 and E2 proteins by modifying their DNA binding activity. Phosphorylation at multiple sites in the N-terminal domain in E1 results in the loss of sequence-specific DNA binding activity, a feature that is also conserved in human papillomavirus (HPV) E1 proteins. The bovine papillomavirus (BPV) E2 protein, when phosphorylated by CK2 on two specific sites in the hinge, also loses its site-specific DNA binding activity. Mutation of these sites in E2 results in greatly increased levels of latent viral DNA replication, indicating that CK2 phosphorylation of E2 is a negative regulator of viral DNA replication during latent viral replication. In contrast, mutation of the N-terminal phosphorylation sites in E1 has no effect on latent viral DNA replication. We propose that the phosphorylation of the N terminus of E1 plays a role only in vegetative viral DNA replication, and consistent with such a role, caspase 3 cleavage of E1, which has been shown to be necessary for vegetative viral DNA replication, restores the DNA binding activity to phosphorylated E1.

Schuck, Stephen; Ruse, Cristian

2013-01-01

170

Oxidative stress mediated toxicity exerted by ethanol-inducible CYP2E1  

SciTech Connect

Induction of CYP2E1 by ethanol is one of the central pathways by which ethanol generates a state of oxidative stress in hepatocytes. To study the biochemical and toxicological actions of CYP2E1, our laboratory established HepG2 cell lines which constitutively overexpress CYP2E1 and characterized these cells with respect to ethanol toxicity. Addition of ethanol or an unsaturated fatty acid such as arachidonic acid or iron was toxic to the CYP2E1-expressing cells but not control cells. This toxicity was associated with elevated lipid peroxidation and could be prevented by antioxidants and inhibitors of CYP2E1. Apoptosis occurred in the CYP2E1-expressing cells exposed to ethanol, arachidonic acid, or iron. Removal of GSH caused a loss of viability in the CYP2E1-expressing cells even in the absence of added toxin or pro-oxidant. This was associated with mitochondrial damage and decreased mitochondrial membrane potential. Low concentrations of iron and arachidonic acid synergistically interacted with CYP2E1 to produce cell toxicity, suggesting these nutrients may act as priming or sensitizing agents to alcohol-induced liver injury. Surprisingly, CYP2E1-expressing cells had elevated GSH levels, due to transcriptional activation of glutamate cysteine ligase. Similarly, levels of catalase, alpha-, and microsomal glutathione transferase were also increased, suggesting that upregulation of these antioxidant genes may reflect an adaptive mechanism to remove CYP2E1-derived oxidants. Using co-cultures, interaction between CYP2E1-derived diffusible mediators to activate collagen production in hepatic stellate cells was found. While it is likely that several mechanisms contribute to alcohol-induced liver injury, the linkage between CYP2E1-dependent oxidative stress, mitochondrial injury, stellate cell activation, and GSH homeostasis may contribute to the toxic action of ethanol on the liver. HepG2 cell lines overexpressing CYP2E1 may be a valuable model to characterize the biochemical and toxicological properties of CYP2E1.

Wu Defeng [Department of Pharmacology and Biological Chemistry, Box 1603, Mount Sinai School of Medicine, One Gustave L. Levy Place, New York, NY 10029 (United States); Cederbaum, Arthur I. [Department of Pharmacology and Biological Chemistry, Box 1603, Mount Sinai School of Medicine, One Gustave L. Levy Place, New York, NY 10029 (United States)]. E-mail: arthur.cederbaum@mssm.edu

2005-09-01

171

The Equine Herpesvirus 2 E1 Open Reading Frame Encodes a Functional Chemokine Receptor  

PubMed Central

Several herpesviruses contain open reading frames (ORFs) that encode potential homologs of eucaryotic genes. Equine herpesvirus 2 (EHV-2) is a gammaherpesvirus related to other lymphotropic herpesviruses such as herpesvirus saimiri and Epstein-Barr virus. The E1 ORF of EHV-2, a G protein-coupled receptor homolog, shows 31 to 47% amino acid identity with known CC chemokine receptors. To investigate whether E1 may encode a functional receptor, we cloned the E1 ORF and expressed it in stably transfected cell lines. We report here the identification of the CC chemokine eotaxin as a functional ligand for the EHV-2 E1 receptor. Chemokines are likely to play a role in the regulation of immune functions in equine hosts during EHV-2 infection and, via interaction with E1, may affect viral replication and/or escape from immune responses.

Camarda, Grazia; Spinetti, Gaia; Bernardini, Giovanni; Mair, Catherine; Davis-Poynter, Nick; Capogrossi, Maurizio C.; Napolitano, Monica

1999-01-01

172

Resolvin E1 maintains macrophage function under cigarette smoke-induced oxidative stress  

PubMed Central

Cigarette smoke (CS) induces oxidative stress, which disables macrophage function. In this study, we examined whether Resolvin E1 (RvE1), a pro-resolving mediator known to enhance macrophage functions, attenuates the damage of macrophages by CS extract (CSE) induced oxidative stress. RvE1 blocked p47phox translocation to plasma membrane induced by CSE in a macrophage cell line, RAW264.7 cells, resulting in suppression of superoxide production. Furthermore, pretreatment of RAW264.7 cells with RvE1 restored the phagocytic activity and reduced cell death induced by treatment of CSE. These results suggest that RvE1 plays important roles in preserving macrophage function under CS-induced oxidative stress.

Takamiya, Rina; Fukunaga, Koichi; Arita, Makoto; Miyata, Jun; Seki, Hiroyuki; Minematsu, Naoto; Suematsu, Makoto; Asano, Koichiro

2012-01-01

173

Earthquake stress drop and laboratory-inferred interseismic strength recovery  

USGS Publications Warehouse

We determine the scaling relationships between earthquake stress drop and recurrence interval tr that are implied by laboratory-measured fault strength. We assume that repeating earthquakes can be simulated by stick-slip sliding using a spring and slider block model. Simulations with static/kinetic strength, time-dependent strength, and rate- and state-variable-dependent strength indicate that the relationship between loading velocity and recurrence interval can be adequately described by the power law VL ??? trn, where n=-1. Deviations from n=-1 arise from second order effects on strength, with n>-1 corresponding to apparent time-dependent strengthening and n<-1 corresponding to weakening. Simulations with rate and state-variable equations show that dynamic shear stress drop ????d scales with recurrence as d????d/dlntr ??? ??e(b-a), where ??e is the effective normal stress, ??=??/??e, and (a-b)=d??ss/dlnV is the steady-state slip rate dependence of strength. In addition, accounting for seismic energy radiation, we suggest that the static shear stress drop ????s scales as d????s/dlntr ??? ??e(1+??)(b-a), where ?? is the fractional overshoot. The variation of ????s with lntr for earthquake stress drops is somewhat larger than implied by room temperature laboratory values of ?? and b-a. However, the uncertainty associated with the seismic data is large and the discrepancy between the seismic observations and the rate of strengthening predicted by room temperature experiments is less than an order of magnitude. Copyright 2001 by the American Geophysical Union.

Beeler, N. M.; Hickman, S. H.; Wong, T. -F.

2001-01-01

174

Resveratrol Downregulates Cyp2e1 and Attenuates Chemically Induced Hepatocarcinogenesis in SD Rats  

PubMed Central

Cyp2e1 plays an important role in chemically induced hepatocarcinogenesis. Resveratrol (REV) is known to prevent diethylnitrosamine (DEN)-induced hepatocarcinogenesis, but its effects on this process induced by DEN and 2-acetylaminofluorene (2-AAF) and the role of Cyp2e1 remain unclear. In this study, glutathione S-transferase placental form (GST-P)-positive foci were used as a marker of hepatocarcinogenesis. REV or diallyl disulfide (DADS, an inhibitor of Cyp2e1) significantly reduced both the area and number of GST-P-positive foci induced by DEN and 2-AAF. Treatment with REV or DADS also markedly decreased the expression of Cyp2e1 in the rat liver. By immunohistochemical staining of serial liver sections, we found that the expression of Cyp2e1 in GST-P-positive foci showed three distinct patterns: decreased in GST-P foci, increased in GST-P foci when compared with surrounding liver tissue and mixed type. The number of GST-P foci with increased Cyp2e1 expression was greater than the number of GST-P foci with decreased Cyp2e1. Protein levels of GST-P and Cyp2e1 were also higher in foci compared with surrounding liver tissue. REV or DADS significantly reduced the expression of GST-P and Cyp2e1 in both foci and surrounding liver tissue. Taken together, these results suggested that REV has a significant inhibitory effect on chemically induced hepatocarcinogenesis, which may be attributed to downregulation of Cyp2e1.

Wu, Xiongfei; Li, Chenggang; Xing, Guozhen; Qi, Xinming; Ren, Jin

2013-01-01

175

Hedgehog Pathway Antagonist 5E1 Binds Hedgehog at the Pseudo-active Site  

PubMed Central

Proper hedgehog (Hh) signaling is crucial for embryogenesis and tissue regeneration. Dysregulation of this pathway is associated with several types of cancer. The monoclonal antibody 5E1 is a Hh pathway inhibitor that has been extensively used to elucidate vertebrate Hh biology due to its ability to block binding of the three mammalian Hh homologs to the receptor, Patched1 (Ptc1). Here, we engineered a murine:human chimeric 5E1 (ch5E1) with similar Hh-binding properties to the original murine antibody. Using biochemical, biophysical, and x-ray crystallographic studies, we show that, like the regulatory receptors Cdon and Hedgehog-interacting protein (Hhip), ch5E1 binding to Sonic hedgehog (Shh) is enhanced by calcium ions. In the presence of calcium and zinc ions, the ch5E1 binding affinity increases 10–20-fold to tighter than 1 nm primarily because of a decrease in the dissociation rate. The co-crystal structure of Shh bound to the Fab fragment of ch5E1 reveals that 5E1 binds at the pseudo-active site groove of Shh with an epitope that largely overlaps with the binding site of its natural receptor antagonist Hhip. Unlike Hhip, the side chains of 5E1 do not directly coordinate the Zn2+ cation in the pseudo-active site, despite the modest zinc-dependent increase in 5E1 affinity for Shh. Furthermore, to our knowledge, the ch5E1 Fab-Shh complex represents the first structure of an inhibitor antibody bound to a metalloprotease fold.

Maun, Henry R.; Wen, Xiaohui; Lingel, Andreas; de Sauvage, Frederic J.; Lazarus, Robert A.; Scales, Suzie J.; Hymowitz, Sarah G.

2010-01-01

176

7 CFR 29.3061 - Strength (tensile).  

Code of Federal Regulations, 2010 CFR

... 2009-01-01 false Strength (tensile). 29.3061 Section 29...Foreign Type 93) § 29.3061 Strength (tensile). The stress a tobacco leaf can bear without tearing. Tensile strength is not an important...

2009-01-01

177

7 CFR 29.3061 - Strength (tensile).  

Code of Federal Regulations, 2010 CFR

... 2010-01-01 false Strength (tensile). 29.3061 Section 29...Foreign Type 93) § 29.3061 Strength (tensile). The stress a tobacco leaf can bear without tearing. Tensile strength is not an important...

2010-01-01

178

Human ubiquitin-activating enzyme (E1): Compensation for heat-labile mouse E1 and its gene localization on the X chromosome  

SciTech Connect

The authors have constructed interspecific somatic cell hybrids between a temperature-sensitive (ts) mutant cell line of mouse FM3A cells, ts85, that has a heat-labile ubiquitin-activating enzyme (E1) and a human diploid fibroblast cell line, IMR-90. A hybrid clone that could grow stably at a nonpermissive temperature (39C) was obtained. Segregation of the hybrid cells at a permissive temperature (33C) gave rise to temperature-sensitive clones. The electrophoresis of extracted histones and karyotype analysis of the segregants revealed a close correlation of the ability to grow at 39C, the presence of uH2A (ubiquitin-H2A semihistone) at 39C, and the presence of the human X chromosome. The sodium dodecyl sulfate-polyacrylamide gel electrophoretic pattern of affinity-purified E1 showed that this hybrid clone contained both human and mouse type E1. Thus they conclude that the functional gene for human E1 is located on the X chromosome.

Kudo, Mami; Enomoto, Takemi; Uf, M. (Univ. of Tokyo (Japan)); Sugasawa, Kaoru; Hanaoka, Fumio (RIKEN Inst., Saitama (Japan)); Hori, Takaaki (National Inst. of Radiological Sciences, Chiba (Japan))

1991-01-01

179

Orthogonal Ubiquitin Transfer through Engineered E1-E2 Cascades for Protein Ubiquitination  

PubMed Central

SUMMARY Protein modification by ubiquitin (UB) controls diverse cellular processes. UB is conjugated to cellular proteins by sequential transfer through an E1-E2-E3 enzymatic cascade. The cross-activities of 2 E1s, 50 E2s and thousands of E3s encoded by the human genome make it difficult to identify the substrate proteins of a specific E3 enzyme in the cell. One way to solve this problem is to engineer an orthogonal UB transfer (OUT) cascade in which the engineered UB (xUB) is relayed by engineered E1, E2 and E3 enzymes (xE1, xE2, xE3) to modify the substrate proteins of a specific E3. Here, we use phage display and mutagenesis to construct xUB-xE1 and xE1-xE2 pairs that are orthogonal to the native E1 and E2 enzymes. Our work on engineering the UB transfer cascades will enable us to use OUT to map the signal transduction networks mediated by protein ubiquitination.

Zhao, Bo; Bhuripanyo, Karan; Zhang, Keya; Kiyokawa, Hiroaki; Schindelin, Hermann; Yin, Jun

2014-01-01

180

Intranuclear location of the adenovirus type 5 E1B 55-kilodalton protein.  

PubMed Central

The intracellular location of the adenovirus type 5 E1B 55-kilodalton (kDa) protein, particularly the question of whether it is associated with nuclear pore complexes, was examined. Fractionation of adenovirus type 5-infected HeLa cell nuclei by an established procedure (N. Dwyer and G. Blobel, J. Cell. Biol. 70:581-591, 1976) yielded one population of E1B 55-kDa protein molecules released by digestion of nuclei with RNase A and a second population recovered in the pore complex-lamina fraction. Free and E1B 55-kDa protein-bound forms of the E4 34-kDa protein (P. Sarnow, C. A. Sullivan, and A. J. Levine, Virology 120:387-394, 1982) were largely recovered in the pore complex-lamina fraction. Nevertheless, the association of E1B 55-kDa protein molecules with this nuclear envelope fraction did not depend on interaction of the E1B 55-kDa protein with the E4 34-kDa protein. Comparison of the immunofluorescence patterns observed with antibodies recognizing the E1B 55-kDa protein or cellular pore complex proteins and of the behavior of these viral and cellular proteins during in situ fractionation suggests that the E1B 55-kDa protein does not become intimately or stably associated with pore complexes in adenovirus-infected cells. Images

Smiley, J K; Young, M A; Flint, S J

1990-01-01

181

Chang’E-1 precision orbit determination and lunar gravity field solution  

NASA Astrophysics Data System (ADS)

In this paper we present results assessing the role of Very Long Baseline Interferometry (VLBI) tracking data through precision orbit determination (POD) during the check-out phase for Chang'E-1, and the lunar gravity field solution CEGM-01 based on the orbital tracking data acquired during the nominal phase of the mission. The POD of Chang'E-1 is performed using S-band two-way Range and Range Rate (R&RR) data, together with VLBI delay and delay rate observations. The role of the VLBI data in the POD of Chang'E-1 is analyzed, and the resulting orbital accuracies are estimated for different solution strategies. The final orbital accuracies proved that the VLBI tracking data can improve the Chang'E-1 POD significantly. Consequently, CEGM-01 based on six-month tracking data during Chang'E-1 nominal mission phase is presented, and the accuracy of the model is assessed by means of the gravity field power spectrum, admittance and coherence between gravity and topography, lunar surface gravity anomaly and POD for both Chang'E-1 and Lunar Prospector (LP). Our analysis indicates that CEGM-01 has significant improvements over a prior model (i.e. GLGM-2), and shows the potential of Chang'E-1 tracking data in high resolution lunar gravity field model solution by combining with SELENE and LP tracking data.

Jianguo, Yan; Jinsong, Ping; Fei, Li; Jianfeng, Cao; Qian, Huang; Lihe, Fung

2010-07-01

182

Intraarterial perfusion of prostaglandin E1 after lumbar sympathectomy or reconstruction on femoropopliteal segment.  

PubMed

Out of 100 patients treated by intraarterial perfusion of prostaglandin E1 we selected 36 cases who have been treated after a lumbar sympathectomy or reconstruction on the femoro-popliteal segment. The patients were in the III and IV stage of occlusive diseases by Fontain. All patients were divided into four groups: (a) prostaglandin E1 after a lumbar sympathectomy (20); (b) prostaglandin E1 after failed femoro-popliteal bypass (8); (c) prostaglandin E1 with patent femoro-popliteal bypass and distal progression of the occlusive disease (3); (d) prostaglandin E1 with previously femoro-popliteal reconstruction and poor run off (5). After intraoperative introduction of a catheter into the superficial femoral artery, profunda femoral artery (a, b), a patent graft (c) or just implanted graft (d), a continuous intraarterial perfusion of prostaglandin E1 was applied, in doses 10 nanograms/kg body weight/minute, in total doses 3000 nanograms. The perfusion time was 48-72 h. The patients were controlled immediately after treatment as well as 1, 3, 6 and 12 months after. Our early and late results of the intraarterial perfusion of prostaglandin E1 proved as a very successful limb salvage procedure. PMID:1765722

Davidovic, L B; Vranes, M R; Lotina, S I; Cernak, I F; Velimirovic, D B; Stojanov, P L; Sindjelic, R P; Sagic, D Z; Cinara, I S

1991-01-01

183

The p75 neurotrophin receptor regulates MC3T3-E1 osteoblastic differentiation.  

PubMed

While the role of p75(NTR) signaling in the regulation of nerve-related cell growth and survival has been well documented, its actions in osteoblasts are poorly understood. In this study, we examined the effects of p75(NTR) on osteoblast proliferation and differentiation using the MC3T3-E1 pre-osteoblast cell line. Proliferation and osteogenic differentiation were significantly enhanced in p75(NTR)-overexpressing MC3T3-E1 cells (p75GFP-E1). In addition, expression of osteoblast-specific osteocalcin (OCN), bone sialoprotein (BSP), and osterix mRNA, ALP activity, and mineralization capacity were dramatically enhanced in p75GFP-E1 cells, compared to wild MC3T3-E1 cells (GFP-E1). To determine the binding partner of p75(NTR) in p75GFP-E1 cells during osteogenic differentiation, we examined the expression of trkA, trkB, and trkC that are known binding partners of p75(NTR), as well as NgR. Pharmacological inhibition of trk tyrosine kinase with the K252a inhibitor resulted in marked reduction in the level of ALPase under osteogenic conditions. The deletion of the GDI binding domain in the p75(NTR)-GFP construct had no effect on mineralization. Taken together, our studies demonstrated that p75(NTR) signaling through the trk tyrosine kinase pathway affects osteoblast functions by targeting osteoblast proliferation and differentiation. PMID:22906707

Mikami, Yoshikazu; Suzuki, Shinnosuke; Ishii, Yumiko; Watanabe, Nobukazu; Takahashi, Tomihisa; Isokawa, Keitaro; Honda, Masaki J

2012-12-01

184

Candida albicans Modulates Host Defense by Biosynthesizing the Pro-Resolving Mediator Resolvin E1  

PubMed Central

Candida albicans is an opportunistic fungal pathogen of humans that resides commensally on epithelial surfaces, but can cause inflammation when pathogenic. Resolvins are a class of anti-inflammatory lipids derived from omega-3 polyunsaturated fatty acids (PUFA) that attenuate neutrophil migration during the resolution phase of inflammation. In this report we demonstrate that C. albicans biosynthesizes resolvins that are chemically identical to those produced by human cells. In contrast to the trans-cellular biosynthesis of human Resolvin E1 (RvE1), RvE1 biosynthesis in C. albicans occurs in the absence of other cellular partners. C. albicans biosynthesis of RvE1 is sensitive to lipoxygenase and cytochrome P450 monoxygenase inhibitors. We show that 10nM RvE1 reduces neutrophil chemotaxis in response to IL-8; 1nM RvE1 enhanced phagocytosis of Candida by human neutrophils, as well as intracellular ROS generation and killing, while having no direct affect on neutrophil motility. In a mouse model of systemic candidiasis, RvE1 stimulated clearance of the fungus from circulating blood. These results reveal an inter-species chemical signaling system that modulates host immune functions and may play a role in balancing host carriage of commensal and pathogenic C. albicans.

Haas-Stapleton, Eric J.; Lu, Yan; Hong, Song; Arita, Makoto; Favoreto, Silvio; Nigam, Santosh; Serhan, Charles N.; Agabian, Nina

2007-01-01

185

Resolvin E1 inhibits neuropathic pain and spinal cord microglial activation following peripheral nerve injury  

PubMed Central

Accumulating evidence indicates that activation of spinal cord microglia plays an important role in the genesis of neuropathic pain. Resolvin E1 (E1) is derived from omega-3 polyunsaturated fatty acid and exhibits potent anti-inflammatory, pro-resolution, and anti-nociceptive effects. We further examined whether RvE1 could reduce neuropathic pain and modulate spinal cord microglial activation. Intrathecal pre-treatment of RvE1 (100 ng) daily for 3 days partially prevented the development of nerve injury-induced mechanical allodynia and up-regulation of IBA-1 (microglial marker) and TNF-? in the spinal cord dorsal horn. Furthermore, intrathecal post-treatment of RvE1 (100 ng), 3 weeks after nerve injury, transiently reduced mechanical allodynia and heat hyperalgesia. Finally, RvE1 blocked lipopolisaccharide-induced microgliosis and TNF-? release in primary micoglial cultures. Our data suggest that RvE1 may attenuate neuropathic pain via inhibiting microglial signaling. Targeting the anti-inflammatory and pro-resolution lipid mediators may offer new options for preventing and treating neuropathic pain.

Xu, Zhen-Zhong; Berta, Temugin; Ji, Ru-Rong

2013-01-01

186

Characterization of human papillomavirus type 11 E1 and E2 proteins expressed in insect cells.  

PubMed Central

The study of human papillomavirus replication has been hampered by the lack of an in vitro system which reliably supports virus replication. Recent results from the bovine papillomavirus (BPV) system indicate that the E1 and E2 proteins are the only viral gene products required for replication. By analogy with simian virus 40 large T antigen, E1 is thought to possess ATPase and helicase activity, which may play a direct role in viral DNA replication. The precise role of E2 is unclear, but it may function in part to help localize E1 to the replication origin. We have initiated a study of replication in the human papillomavirus type 11 system which, by analogy to BPV, has focused on the E1 and E2 proteins of this virus. We have expressed the full-length E1 and E2 proteins in Sf9 insect cells by using a baculovirus expression vector. Both the 80-kDa E1 protein and the 42.5-kDa E2 protein are nuclear phosphoproteins. The E1 and E2 proteins form a heteromeric complex within the insect cells, and both proteins localize to a DNA fragment which contains the viral origin of replication. In addition, we have detected an E1-associated ATPase and GTPase activity, which is likely part of an energy-generating system for the helicase activity which is predicted for this protein. The human papillomavirus type 11 E1 and E2 proteins possess the same replication-associated activities exhibited by the corresponding BPV proteins, suggesting that the replication activities of these viruses are tightly conserved. Images

Bream, G L; Ohmstede, C A; Phelps, W C

1993-01-01

187

Adenovirus E1A Directly Targets the E2F/DP-1 Complex?  

PubMed Central

Deregulation of the cell cycle is of paramount importance during adenovirus infection. Adenovirus normally infects quiescent cells and must initiate the cell cycle in order to propagate itself. The pRb family of proteins controls entry into the cell cycle by interacting with and repressing transcriptional activation by the E2F transcription factors. The viral E1A proteins indirectly activate E2F-dependent transcription and cell cycle entry, in part, by interacting with pRb and family members to free the E2Fs. We report here that an E1A 13S isoform can unexpectedly activate E2F-responsive gene expression independently of binding to the pRb family of proteins. We demonstrate that E1A binds to E2F/DP-1 complexes through a direct interaction with DP-1. E1A appears to utilize this binding to recruit itself to E2F-regulated promoters, and this allows the E1A 13S protein, but not the E1A 12S protein, to activate transcription independently of interaction with pRb. Importantly, expression of E1A 13S, but not E1A 12S, led to significant enhancement of E2F4 occupancy of E2F sites of two E2F-regulated promoters. These observations identify a novel mechanism by which adenovirus deregulates the cell cycle and suggest that E1A 13S may selectively activate a subset of E2F-regulated cellular genes during infection.

Pelka, Peter; Miller, Matthew S.; Cecchini, Matthew; Yousef, Ahmed F.; Bowdish, Dawn M.; Dick, Fred; Whyte, Peter; Mymryk, Joe S.

2011-01-01

188

Systematic exploration of ubiquitin sequence, e1 activation efficiency, and experimental fitness in yeast.  

PubMed

The complexity of biological interaction networks poses a challenge to understanding the function of individual connections in the overall network. To address this challenge, we developed a high-throughput reverse engineering strategy to analyze how thousands of specific perturbations (encompassing all point mutations in a central gene) impact both a specific edge (interaction to a directly connected node) and an overall network function. We analyzed the effects of ubiquitin mutations on activation by the E1 enzyme and compared these to effects on yeast growth rate. Using this approach, we delineated ubiquitin mutations that selectively impacted the ubiquitin-E1 edge. We find that the elasticity function relating the efficiency of ubiquitin-E1 interaction to growth rate is non-linear and that a greater than 50-fold decrease in E1 activation efficiency is required to reduce growth rate by 2-fold. Despite the robustness of fitness to decreases in E1 activation efficiency, the effects of most ubiquitin mutations on E1 activation paralleled the effects on growth rate. Our observations indicate that most ubiquitin mutations that disrupt E1 activation also disrupt other functions. The structurally characterized ubiquitin-E1 interface encompasses the interfaces of ubiquitin with most other known binding partners, and we propose that this enables E1 in wild-type cells to selectively activate ubiquitin protein molecules capable of binding to other partners from the cytoplasmic pool of ubiquitin protein that will include molecules with chemical damage and/or errors from transcription and translation. PMID:24862281

Roscoe, Benjamin P; Bolon, Daniel N A

2014-07-29

189

The E1 glycoprotein of an avian coronavirus is targeted to the cis Golgi complex.  

PubMed

It was previously reported that the E1 protein of an avian coronavirus was targeted to the juxtanuclear region in COS cells expressing the protein from cloned cDNA, suggesting that the protein contains information for targeting to the Golgi complex. The first of three membrane-spanning domains was required for intracellular targeting, because a mutant E1 (delta m1,2) lacking this domain was delivered to the plasma membrane. We have used immunoelectron microscopy to localize the wild-type E1 protein within Golgi elements of COS cells and AtT-20 cells expressing these proteins from recombinant vaccinia vectors. By immunoperoxidase and immunogold labeling, the wild-type E1 protein was localized to one or two cisternae located on one side of the Golgi stack that could be identified as the cis side in AtT-20 cells. In contrast, the mutant E1 protein was detected in all cisternae across the stack as well as at the plasma membrane. When the E1 proteins were immunoprecipitated and subjected to digestion with endoglycosidase H, the majority of the wild-type E1 glycoprotein was endoglycosidase H sensitive, whereas the majority of the mutant E1 was processed to an endoglycosidase H-resistant, polylactosaminoglycan-containing form. The findings indicate that the wild-type E1 protein is specifically targeted to cis Golgi cisternae and are consistent with the assumption that the first membrane-spanning domain is required for targeting to the cis Golgi. PMID:2169615

Machamer, C E; Mentone, S A; Rose, J K; Farquhar, M G

1990-09-01

190

Precision measurement of the electromagnetic dipole strengths in Be11  

NASA Astrophysics Data System (ADS)

The electromagnetic dipole strength in Be11 between the bound states has been measured using low-energy projectile Coulomb excitation at bombarding energies of 1.73 and 2.09 MeV/nucleon on a Pt196 target. An electric dipole transition probability B(E1;1/2??1/2+)=0.102(2) e2fm was determined using the semi-classical code Gosia, and a value of 0.098(4) e2fm was determined using the Extended Continuum Discretized Coupled Channels method with the quantum mechanical code FRESCO. These extracted B(E1) values are consistent with the average value determined by a model-dependent analysis of intermediate energy Coulomb excitation measurements and are approximately 14% lower than that determined by a lifetime measurement. The much-improved precisions of 2% and 4% in the measured B(E1) values between the bound states deduced using Gosia and the Extended Continuum Discretized Coupled Channels method, respectively, compared to the previous accuracy of ˜10% will help in our understanding of and better improve the realistic inter-nucleon interactions.

Kwan, E.; Wu, C. Y.; Summers, N. C.; Hackman, G.; Drake, T. E.; Andreoiu, C.; Ashley, R.; Ball, G. C.; Bender, P. C.; Boston, A. J.; Boston, H. C.; Chester, A.; Close, A.; Cline, D.; Cross, D. S.; Dunlop, R.; Finlay, A.; Garnsworthy, A. B.; Hayes, A. B.; Laffoley, A. T.; Nano, T.; Navrátil, P.; Pearson, C. J.; Pore, J.; Quaglioni, S.; Svensson, C. E.; Starosta, K.; Thompson, I. J.; Voss, P.; Williams, S. J.; Wang, Z. M.

2014-05-01

191

Strength of Nanotubes and Megacables  

NASA Astrophysics Data System (ADS)

In this chapter my findings [mainly reported in N. Pugno, J. Phys.- Condens. Matter, 18, S1971-S1990 (2006); N. Pugno, Acta Mater. 55, 5269-5279 (2007); N. Pugno, Nano Today 2, 44-47 (2007)] on the mechanical strength of nanotubes and megacables are reviewed, with an eye to the challenging project of the carbon nanotube-based space elevator megacable. Accordingly, basing the design of the megacable on the theoretical strength of a single carbon nanotube, as originally proposed at the beginning of the third millennium, has been demonstrated to be naïve. The role on the fracture strength of thermodynamically unavoidable atomistic defects with different size and shape is thus here quantified on brittle fracture both numerically (with ad hoc hierarchical simulations) and theoretically (with quantized fracture theories), for nanotubes and nanotube bundles. Fatigue, elasticity, non-asymptotic regimes, elastic-plasticity, rough cracks, finite domains and size-effects are also discussed.

Pugno, Nicola M.

192

Oscillator strengths for Si II  

NASA Astrophysics Data System (ADS)

New accurate results are presented for absorption oscillator strengths of Si II resonance lines. In these ab initio calculations, an extensive basis set of 67 electronic configuration are employed, including fine-structure states and relativistic effects in the Breit-Pauli approximation. For the strong Si II lines, good agreement is found with previous LS-coupling f-values of Dufton et al. (1983). Oscillator strengths of selected weaker lines disagree in some cases with empirically determined f-values by Shull, Snow, and York (1981) and by Van Buren (1986). The theoretical results are combined with curve-of-growth analyses of Copernicus and IUE data to yield a list of recommended Si II oscillator strengths consistent with the errors in both theoretical and observational analyses. These f-values have been used (Van Steenberg and Shull) for a Galactic survey of interstellar silicon abundances with the International Ultraviolet Explorer satellite.

Luo, Ding; Pradhan, Anil K.; Shull, J. Michael

1988-12-01

193

Oscillator strengths for Si II  

NASA Technical Reports Server (NTRS)

New accurate results are presented for absorption oscillator strengths of Si II resonance lines. In these ab initio calculations, an extensive basis set of 67 electronic configuration are employed, including fine-structure states and relativistic effects in the Breit-Pauli approximation. For the strong Si II lines, good agreement is found with previous LS-coupling f-values of Dufton et al. (1983). Oscillator strengths of selected weaker lines disagree in some cases with empirically determined f-values by Shull, Snow, and York (1981) and by Van Buren (1986). The theoretical results are combined with curve-of-growth analyses of Copernicus and IUE data to yield a list of recommended Si II oscillator strengths consistent with the errors in both theoretical and observational analyses. These f-values have been used (Van Steenberg and Shull) for a Galactic survey of interstellar silicon abundances with the International Ultraviolet Explorer satellite.

Luo, Ding; Pradhan, Anil K.; Shull, J. Michael

1988-01-01

194

Strength of Concrete in High Strength Revibrated Walls.  

National Technical Information Service (NTIS)

Properly placed and adequately vibrated concrete is compact and uniform. However conditions of casting and compaction can vary with the type of structure. Previous investigations made on walls had shown that the strength of concrete in the top part was lo...

J. Bhargava

1969-01-01

195

140. Enhanced Cell Killing Effect of E1 Modified Adenoviruses Expressing HSV-TK Suicide Gene  

Microsoft Academic Search

To combine the advantages of the prodrug\\/suicide gene approach with that of replicating adenoviruses, we have developed replicating adenoviral vectors harboring HSV-TK, generating Ad-?E1B19-TK, Ad-?E1B55-TK, Ad-?E1B19\\/55-TK adenoviruses. Infection with adenoviruses expressing HSV-TK increased the sensitivity of cells to GCV. Cell killing assay was used to compare the combined therapy with the two single therapy modalities and non-treated controls in human

Oh-Joon Kwon; Dong Hyun Ko; Jing Hwa Huang; Il-Kyu Choi; Sung-Mi Jung; Joo-Hang Kim; Byoung Chul Cho; Chae-Ok Yun

2006-01-01

196

Absence of NR2E1 mutations in patients with aniridia  

PubMed Central

Purpose Nuclear receptor 2E1 (NR2E1) is a transcription factor with many roles during eye development and thus may be responsible for the occurrence of certain congenital eye disorders in humans. To test this hypothesis, we screened NR2E1 for candidate mutations in patients with aniridia and other congenital ocular malformations (anterior segment dysgenesis, congenital optic nerve malformation, and microphthalmia). Methods The NR2E1 coding region, 5? and 3? untranslated regions (UTRs), exon flanking regions including consensus splice sites, and six evolutionarily conserved non-coding candidate regulatory regions were analyzed by sequencing 58 probands with aniridia of whom 42 were negative for PAX6 mutations. Nineteen probands with anterior segment dysgenesis, one proband with optic nerve malformation, and two probands with microphthalmia were also sequenced. The control population comprised 376 healthy individuals. All sequences were analyzed against the GenBank sequence AL078596.8 for NR2E1. In addition, the coding region and flanking intronic sequences of FOXE3, FOXC1, PITX2, CYP1B1, PAX6, and B3GALTL were sequenced in one patient and his relatives. Results Sequencing analysis showed 17 NR2E1 variants including two novel rare non-coding variants (g.-1507G>A, g.14258C>T), and one novel rare coding variant (p.Arg274Gly). The latter was present in a male diagnosed with Peters’ anomaly who subsequently was found to have a known causative mutation for Peters’ plus syndrome in B3GALTL (c.660+1G>A). In addition, the NR2E1 novel rare variant Arg274Gly was present in the unaffected mother of the patient but absent in 746 control chromosomes. Conclusions We eliminated a major role for NR2E1 regulatory and coding mutations in aniridia and found a novel rare coding variant in NR2E1. In addition, we found no coding region variation in the control population for NR2E1, which further supports its previously reported high level of conservation and low genetic diversity. Future NR2E1 studies in ocular disease groups such as those involving retinal and optic nerve abnormalities should be undertaken to determine whether NR2E1 plays a role in these conditions.

Corso-Diaz, Ximena; Borrie, Adrienne E.; Bonaguro, Russell; Schuetz, Johanna M.; Rosenberg, Thomas; Jensen, Hanne; Brooks, Brian P.; MacDonald, Ian M.; Pasutto, Francesca; Walter, Michael A.; Gr?nskov, Karen; Brooks-Wilson, Angela

2012-01-01

197

The effects of prostaglandin E1, bradykinin and histamine on canine synovial vascular permeability.  

PubMed Central

1 The relative effects of prostaglandin E1, bradykinin and histamine on canine synovial vascular permeability were investigated by a method based on the measurement of the amounts of radiolabelled dextran (molecular weight 20,000) leaking from the circulation into the synovial cavity. 2 Bradykinin, prostaglandin E1 and histamine in that order of potency all increased synovial vascular permeability. Threshold concentrations were 0.3 micrometer, 3 micrometer and 30 micrometer respectively. 3 The effects of infusion of prostaglandin E1 combined with either bradykinin or histamine were greater than mere summation.

Grennan, D M; Mitchel, W; Miller, W; Zeitlin, I J

1977-01-01

198

Oscillator strengths for Be I  

SciTech Connect

The electric dipole oscillator strengths for lines between some singlet and triplet levels have been calculated using the weakest bound electron potential model theory and the quantum defect orbital theory for Be I. In the calculations both multiplet and fine structure transitions are studied. We employed both the numerical Coulomb approximation method and numerical non-relativistic Hartree-Fock wavefunctions for expectation values of radii. The necessary energy values have been taken from experimental energy data in the literature. The calculated oscillator strengths have been compared with available theoretical results. A good agreement with the results in the literature has been obtained.

Ates, Sule, E-mail: suleates@selcuk.edu.tr; Oezarslan, Selma; Celik, Gueltekin; Taser, Mehmet

2012-07-15

199

The torsional strength of wings  

NASA Technical Reports Server (NTRS)

This report describes a simple method for calculating the position of the elastic axis of a wing structure having any number of spars. It is shown that strong drag bracing near the top and bottom of a wing greatly increases the torsional strength. An analytical procedure for finding the contribution of the drag bracing to the torsional strength and stiffness is described, based upon the principle of least work, and involving only one unknown quantity. A coefficient for comparing the torsional rigidity of different wings is derived in this report.

Burgess, C P

1930-01-01

200

Identification of the catalytic glutamate in the E1 component of human pyruvate dehydrogenase.  

PubMed

The pyruvate dehydrogenase complex catalyzes the conversion of pyruvate to acetyl-CoA. The first component (E1) converts pyruvate to bound acetaldehyde using thiamine diphosphate (ThDP) and Mg2+ as cofactors. There is no 3D structure of E1 available but those of other ThDP-dependent enzymes show some similarities including a glutamate residue that assists in ThDP activation. Eukaryotic E1 has an alpha2beta2 structure and the conserved Glu89 of the beta-subunit was identified as a possible catalytic residue by sequence alignment. Human E1 was expressed in Escherichia coli and purified. Mutating Glu89 to glutamine, aspartate and alanine markedly reduces catalytic activity and the affinity for ThDP, consistent with a role as the catalytic glutamate. PMID:9824306

Fang, R; Nixon, P F; Duggleby, R G

1998-10-23

201

26 CFR 1.1031(e)-1 - Exchange of livestock of different sexes.  

Code of Federal Regulations, 2011 CFR

...false Exchange of livestock of different sexes. 1.1031(e)-1 Section 1.1031...1 Exchange of livestock of different sexes. Section 1031(e) provides that livestock of different sexes are not property of like kind....

2011-04-01

202

26 CFR 1.1031(e)-1 - Exchange of livestock of different sexes.  

Code of Federal Regulations, 2010 CFR

...true Exchange of livestock of different sexes. 1.1031(e)-1 Section 1.1031...1 Exchange of livestock of different sexes. Section 1031(e) provides that livestock of different sexes are not property of like kind....

2010-04-01

203

26 CFR 1.1031(e)-1 - Exchange of livestock of different sexes.  

Code of Federal Regulations, 2012 CFR

...false Exchange of livestock of different sexes. 1.1031(e)-1 Section 1.1031...1 Exchange of livestock of different sexes. Section 1031(e) provides that livestock of different sexes are not property of like kind....

2012-04-01

204

17 CFR 270.10e-1 - Death, disqualification, or bona fide resignation of directors.  

Code of Federal Regulations, 2010 CFR

...Death, disqualification, or bona fide resignation of directors. 270.10e-1 Section...Death, disqualification, or bona fide resignation of directors. If a registered investment...death, disqualification, or bona fide resignation of any director, does not...

2010-04-01

205

17 CFR 270.10e-1 - Death, disqualification, or bona fide resignation of directors.  

Code of Federal Regulations, 2010 CFR

...Death, disqualification, or bona fide resignation of directors. 270.10e-1 Section...Death, disqualification, or bona fide resignation of directors. If a registered investment...death, disqualification, or bona fide resignation of any director, does not...

2009-04-01

206

Coronavirus E1 glycoprotein expressed from cloned cDNA localizes in the Golgi region.  

PubMed Central

Cloned cDNA encoding the membrane glycoprotein E1 of the coronavirus mouse hepatitis virus strain A59 was expressed transiently in a monkey fibroblast cell line (COS) by using a simian virus 40-based vector. As determined by indirect immunofluorescence microscopy, the E1 protein accumulated intracellularly in a perinuclear region coincident with a Golgi marker. The same three species of E1 that occur in virus-infected cells were also found in transfected cells. These are one unglycosylated form and two apparently O-glycosylated forms that could be labeled in a tunicamycin-resistant fashion with [3H]glucosamine. Because O glycosylation occurs posttranslationally in the Golgi apparatus, we could show, by monitoring the rate of acquisition of oligosaccharides, that the transport of E1 from the rough endoplasmic reticulum to the Golgi apparatus had a half time of between 15 and 30 min. Images

Rottier, P J; Rose, J K

1987-01-01

207

The C-terminal region of E1A: a molecular tool for cellular cartography.  

PubMed

The adenovirus E1A proteins function via protein-protein interactions. By making many connections with the cellular protein network, individual modules of this virally encoded hub reprogram numerous aspects of cell function and behavior. Although many of these interactions have been thoroughly studied, those mediated by the C-terminal region of E1A are less well understood. This review focuses on how this region of E1A affects cell cycle progression, apoptosis, senescence, transformation, and conversion of cells to an epithelial state through interactions with CTBP1/2, DYRK1A/B, FOXK1/2, and importin-?. Furthermore, novel potential pathways that the C-terminus of E1A influences through these connections with the cellular interaction network are discussed. PMID:22292450

Yousef, Ahmed F; Fonseca, Gregory J; Cohen, Michael J; Mymryk, Joe S

2012-04-01

208

26 CFR 1.1031(e)-1 - Exchange of livestock of different sexes.  

Code of Federal Regulations, 2013 CFR

...false Exchange of livestock of different sexes. 1.1031(e)-1 Section 1.1031...1 Exchange of livestock of different sexes. Section 1031(e) provides that livestock of different sexes are not property of like kind....

2013-04-01

209

26 CFR 301.6230(e)-1 - Tax matters partner required to furnish names.  

Code of Federal Regulations, 2013 CFR

...Tax matters partner required to furnish names. 301.6230(e)-1 Section 301...Tax matters partner required to furnish names. (a) In general. If a notice...Service office that issued the notice the name, address, profits interest,...

2013-04-01

210

An interlaminar tension strength specimen  

NASA Technical Reports Server (NTRS)

This paper describes a technique to determine interlaminar tension strength, sigma(sub 3c) of a fiber reinforced composite material using a curved beam. The specimen was a unidirectional curved beam, bent 90 degrees, with straight arms. Attached to each arm was a hinged loading mechanism which was held by the grips of a tensile testing machine. Geometry effects of the specimen, including the effects of loading arm length, inner radius, thickness, and width, were studied. The data sets fell into two categories: low strength corresponding to a macroscopic flaw related failure and high strength corresponding to a microscopic flaw related failure. From the data available, the loading arm length had no effect on sigma(sub 3c). The inner radius was not expected to have a significant effect on sigma(sub 3c), but this conclusion could not be confirmed because of differences in laminate quality for each curve geometry. The thicker specimens had the lowest value of sigma(sub 3c) because of poor laminate quality. Width was found to affect the value of sigma(sub 3c) only slightly. The wider specimens generally had a slightly lower strength since more material was under high stress, and hence, had a larger probability of containing a significant flaw.

Jackson, Wade C.; Martin, Roderick H.

1992-01-01

211

Withdrawal Strength of Threaded Nails  

Microsoft Academic Search

Threaded nails are used in wood construction because of their superior performance, but relatively few tests have been conducted on nails larger than 12d (3.76 mm diameter). Experience has suggested that threaded nail withdrawal design values are too conservative. The Forest Products Laboratory and Washington State University have been cooperatively characterizing the strength of threaded nails over a range of

Douglas R. Rammer; Steve G. Winistorfer; Donald A. Bender

2001-01-01

212

Tensile strength of hybrid composites  

Microsoft Academic Search

This paper presents an approximate, statistical analysis for the tensile strength of unidirectional hybrid composite materials consisting of two-dimensional arrays of alternating low elongation and high elongation fibres in a common matrix. Expressions for ineffective length and fibre strain concentration factor in hybrid composites are developed. The analysis identifies a number of important material properties that affect the failure process

Carl Zweben; E. L du Pont de Nemours

1977-01-01

213

Building Strengths through Adventure Education  

ERIC Educational Resources Information Center

Campbell Loughmiller (1906-1993) is widely recognized as a leader in therapeutic work with troubled youngsters in outdoor settings. Rejecting punitive or institutional models of intervention, Loughmiller set out to demonstrate that every young person has strengths, desires to make positive changes, can grow in responsibility, and contribute to…

Loughmiller, Grover C.

2007-01-01

214

Evaluation of Tensile Strength Testing.  

National Technical Information Service (NTIS)

The report contains a summary of the activities related to the development, application and use of the splitting tensile test and of the flexure beam test to estimate the tensile strength of portland cement concrete pavement. Information related to the de...

A. H. Meyer D. W. Fowler L. M. Melis

1985-01-01

215

Strength Stability Vibrations. Volume 2.  

National Technical Information Service (NTIS)

This is the second volume of a 3-volume handbook edited by I. A. Birger, Doctor of Technical Sciences and Ya. G. Panvoko, Corresponding Member, Academy of Sciences, Latvian SSR. The methods of designing for strength thin composite, anisotropic, and sandwi...

A. Y. Aleksandrov I. A. Birger S. A. Ambartsumyan V. L. Biderman V. V. Bolotin

1970-01-01

216

Natural history of the E1-like superfamily: implication for adenylation, sulfur transfer and ubiquitin conjugation  

PubMed Central

The E1-like superfamily is central to ubiquitin (Ub) conjugation, biosynthesis of cysteine, thiamine and MoCo and several secondary metabolites. Yet, its functional diversity and evolutionary history is not well-understood. We develop a natural classification of this superfamily and use it to decipher the major adaptive trends occurring in the evolution of the E1-like superfamily. Within the Rossmann fold, E1-like proteins are closest to NAD(P)/FAD-dependent dehydrogenases and S-AdoMet-dependent methyltransferases. Hence, their phosphotransfer activity is an independent catalytic “invention” with respect to such activities seen in other Rossmannoid folds. Sequence and structure analysis reveals a striking diversity of residues and structures involved in adenylation, sulfotransfer and substrate-binding between different E1-like families, allowing us to predict previously uncharacterized functional adaptations. E1-like proteins are fused to several previously undetected domains, such as a predicted sulfur transfer domain containing a novel superfamily of the TATA-binding protein fold, different types of catalytic domains, a novel winged helix-turn-helix domain and potential adaptor domains related to Ub conjugation. Based on these fusions we develop a generalized model for the linking of E1 catalyzed adenylation/thiolation with further down-stream reactions. This is likely to involve a dynamic interplay between the E1 active sites and diverse fused C-terminal domains. We also predict participation of E1-like domains in previously uncharacterized bacterial secondary metabolism pathways, new cysteine biosynthesis systems, such as those associated with archaeal O-phosphoseryl tRNA, metal-sulfur cluster assembly (e.g. in nitrogen fixation) and Ub-conjugation. Evolutionary reconstructions suggest that the last universal common ancestor (LUCA) contained a single E1-like domain possessing both phosphotransfer and thiolating activities and participating in multiple sulfotransfer reactions. The E1-like superfamily subsequently expanded to include 26 families clustering into three major radiations. These are broadly involved in ubiquitin activation, cofactor and cysteine biosynthesis, and biosynthesis of secondary metabolites. In light of this we present evidence that in eukaryotes other E1-like enzymes, such as Urm1, were independently recruited for Ubl conjugation, probably functioning without conventional E2-like enzymes.

Burroughs, A. Maxwell; Iyer, Lakshminarayan M.; Aravind, L.

2009-01-01

217

Crystal Structure of the E1 Component of the Escherichia coli 2Oxoglutarate Dehydrogenase Multienzyme Complex  

Microsoft Academic Search

The thiamine-dependent E1o component (EC 1.2.4.2) of the 2-oxoglutarate dehydrogenase complex catalyses a rate-limiting step of the tricarboxylic acid cycle (TCA) of aerobically respiring organisms. We describe the crystal structure of Escherichia coli E1o in its apo and holo forms at 2.6 Å and 3.5 Å resolution, respectively. The structures reveal the characteristic fold that binds thiamine diphosphate and resemble closely the

René A. W. Frank; Amanda J. Price; Fred D. Northrop; Richard N. Perham; Ben F. Luisi

2007-01-01

218

Expression and characterization of Acidothermus cellulolyticus E1 endoglucanase in transgenic duckweed Lemna minor 8627  

Microsoft Academic Search

Endoglucanase E1 from Acidothermus cellulolyticus was expressed cytosolically under control of the cauliflower mosaic virus 35S promoter in transgenic duckweed, Lemna minor 8627 without any obvious observable phenotypic effects on morphology or rate of growth. The recombinant enzyme co-migrated with the purified catalytic domain fraction of the native E1 protein on western blot analysis, revealing that the cellulose-binding domain was

Ye Sun; Jay J. Cheng; Michael E. Himmel; Christopher D. Skory; William S. Adney; Steven R. Thomas; Brent Tisserat; Yufuko Nishimura; Yuri T. Yamamoto

2007-01-01

219

CYP2E1-dependent elevation of serum cholesterol, triglycerides, and hepatic bile acids by isoniazid  

SciTech Connect

Isoniazid is the first-line medication in the prevention and treatment of tuberculosis. Isoniazid is known to have a biphasic effect on the inhibition–induction of CYP2E1 and is also considered to be involved in isoniazid-induced hepatotoxicity. However, the full extent and mechanism of involvement of CYP2E1 in isoniazid-induced hepatotoxicity remain to be thoroughly investigated. In the current study, isoniazid was administered to wild-type and Cyp2e1-null mice to investigate the potential toxicity of isoniazid in vivo. The results revealed that isoniazid caused no hepatotoxicity in wild-type and Cyp2e1-null mice, but produced elevated serum cholesterol and triglycerides, and hepatic bile acids in wild-type mice, as well as decreased abundance of free fatty acids in wild-type mice and not in Cyp2e1-null mice. Metabolomic analysis demonstrated that production of isoniazid metabolites was elevated in wild-type mice along with a higher abundance of bile acids, bile acid metabolites, carnitine and carnitine derivatives; these were not observed in Cyp2e1-null mice. In addition, the enzymes responsible for bile acid synthesis were decreased and proteins involved in bile acid transport were significantly increased in wild-type mice. Lastly, treatment of targeted isoniazid metabolites to wild-type mice led to similar changes in cholesterol, triglycerides and free fatty acids. These findings suggest that while CYP2E1 is not involved in isoniazid-induced hepatotoxicity, while an isoniazid metabolite might play a role in isoniazid-induced cholestasis through enhancement of bile acid accumulation and mitochondria ?-oxidation. -- Highlights: ? Isoniazid metabolites were elevated only in wild-type mice. ? Isoniazid caused no hepatotoxicity in wild-type and Cyp2e1-null mice. ? Isoniazid elevated serum cholesterol and triglycerides, and hepatic bile acids. ? Bile acid transporters were significantly decreased in isoniazid-treated mice.

Cheng, Jie; Krausz, Kristopher W. [Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States)] [Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Li, Feng; Ma, Xiaochao [Department of Pharmacology, Toxicology and Therapeutics, The University of Kansas Medical Center, 4089 KLSIC, MS 1018, 3901 Rainbow Boulevard, Kansas City, KS 66160 (United States)] [Department of Pharmacology, Toxicology and Therapeutics, The University of Kansas Medical Center, 4089 KLSIC, MS 1018, 3901 Rainbow Boulevard, Kansas City, KS 66160 (United States); Gonzalez, Frank J., E-mail: fjgonz@helix.nih.gov [Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States)

2013-01-15

220

Resveratrol Stimulates the Proliferation and Differentiation of Osteoblastic MC3T3-E1 Cells  

Microsoft Academic Search

Nutritional and pharmacological factors are needed to prevent bone loss that occurs with increasing age. The chemical compounds that act on bone metabolism as nutrients in food, however, are poorly understood. The effect of resveratrol, a natural phytoestrogen, on the proliferation and differentiation of osteoblastic MC3T3-E1 cells was studied. Resveratrol dose-dependently increased DNA synthesis (10?9?10?7M) of MC3T3-E1 cells. In addition,

Kenichi Mizutani; Katsumi Ikeda; Yasuhiro Kawai; Yukio Yamori

1998-01-01

221

Viral E1 and E2 Proteins Support Replication of Homologous and Heterologous Papillomaviral Origins  

Microsoft Academic Search

We have shown that E1 and E2 proteins of human papillomavirus type 11 (HPV-11) were essential to support the replication of the homologous viral origin (ori) in a transient replication assay, similar to reports on bovine papillomavirus type 1 (BPV-1). Unexpectedly, matched or even mixed combinations of E1 and E2 proteins from HPV-11 or BPV-1 replicated either ori in human,

Cheng-Ming Chiang; Mart Ustav; Arne Stenlund; Thau F. Ho; Thomas R. Broker; Louise T. Chow

1992-01-01

222

CYP2E1-mediated mechanism of anti-genotoxicity of the broccoli constituent sulforaphane  

Microsoft Academic Search

^To whom requests for reprints should be addressed The broccoli constituent sulforaphane (l-isothiocyanate-4- methylsulfinylbutane) has previously been shown to protect rats against 9,10-dimethyl-lr2-benz(a)anthracene tumori- genesis, thought to be due, at least in part, to induction of phase II detoxificatio n. We investigated the ability of sulforaphane to also inhibit the phase I enzyme cytochrome P450 isoenzyme 2E1 (CYP2E1), which is

Silvia Barcelo; John M. Gardiner; Andreas Gescher; J. Kevin Chipmanw

1996-01-01

223

Functional processing and secretion of Chikungunya virus E1 and E2 glycoproteins in insect cells  

PubMed Central

Background Chikungunya virus (CHIKV) is a mosquito-borne, arthrogenic Alphavirus that causes large epidemics in Africa, South-East Asia and India. Recently, CHIKV has been transmitted to humans in Southern Europe by invading and now established Asian tiger mosquitoes. To study the processing of envelope proteins E1 and E2 and to develop a CHIKV subunit vaccine, C-terminally his-tagged E1 and E2 envelope glycoproteins were produced at high levels in insect cells with baculovirus vectors using their native signal peptides located in CHIKV 6K and E3, respectively. Results Expression in the presence of either tunicamycin or furin inhibitor showed that a substantial portion of recombinant intracellular E1 and precursor E3E2 was glycosylated, but that a smaller fraction of E3E2 was processed by furin into mature E3 and E2. Deletion of the C-terminal transmembrane domains of E1 and E2 enabled secretion of furin-cleaved, fully processed E1 and E2 subunits, which could then be efficiently purified from cell culture fluid via metal affinity chromatography. Confocal laser scanning microscopy on living baculovirus-infected Sf21 cells revealed that full-length E1 and E2 translocated to the plasma membrane, suggesting similar posttranslational processing of E1 and E2, as in a natural CHIKV infection. Baculovirus-directed expression of E1 displayed fusogenic activity as concluded from syncytia formation. CHIKV-E2 was able to induce neutralizing antibodies in rabbits. Conclusions Chikungunya virus glycoproteins could be functionally expressed at high levels in insect cells and are properly glycosylated and cleaved by furin. The ability of purified, secreted CHIKV-E2 to induce neutralizing antibodies in rabbits underscores the potential use of E2 in a subunit vaccine to prevent CHIKV infections.

2011-01-01

224

Calculation of energy levels, {ital E}1 transition amplitudes, and parity violation in francium  

Microsoft Academic Search

Many-body perturbation theory in the screened Coulomb interaction was used to calculate energy levels, {ital E}1 trransition amplitudes, and the parity-nonconserving (PNC) {ital E}1 amplitude of the 7{ital s}-8{ital s} transition in francium. The method takes into account the core-polarization effect, the second-order correlations, and the three dominating sequences of higher-order correlation diagrams: screening of the electron-electron interaction, particle-hole interaction,

V. A. Dzuba; V. V. Flambaum; O. P. Sushkov

1995-01-01

225

Nuclear level densities and {gamma}-ray strength functions in {sup 44,45}Sc  

SciTech Connect

The scandium isotopes {sup 44,45}Sc were studied with the {sup 45}Sc({sup 3}He, {alpha}{gamma}){sup 44}Sc and {sup 45}Sc({sup 3}He, {sup 3}He{sup '}{gamma}){sup 45}Sc reactions, respectively. The nuclear level densities and {gamma}-ray strength functions have been extracted using the Oslo method. The experimental level densities are compared to calculated level densities obtained from a microscopic model based on BCS quasiparticles within the Nilsson level scheme. This model also gives information about the parity distribution and the number of broken Cooper pairs as a function of excitation energy. The experimental {gamma}-ray strength functions are compared to theoretical models of the E1, M1, and E2 strength and to data from ({gamma}, n) and ({gamma},p) experiments. The strength functions show an enhancement at low {gamma} energies that cannot be explained by the present standard models.

Larsen, A. C.; Guttormsen, M.; Ingebretsen, F.; Messelt, S.; Rekstad, J.; Siem, S.; Syed, N. U. H. [Department of Physics, University of Oslo, P. O. Box 1048 Blindern, N-0316 Oslo (Norway); Chankova, R. [North Carolina State University, Raleigh, North Carolina 27695, USA and Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708 (United States); Loennroth, T. [Department of Physics, Angstrombo Akademi University, FIN-20500 Angstrombo (Finland); Schiller, A. [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States); Voinov, A. [Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701 (United States) and Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, RU-141980 Dubna, Moscow region (Russian Federation)

2007-10-15

226

Crystal structure of the E1 component of the Escherichia coli 2-oxoglutarate dehydrogenase multienzyme complex.  

PubMed

The thiamine-dependent E1o component (EC 1.2.4.2) of the 2-oxoglutarate dehydrogenase complex catalyses a rate-limiting step of the tricarboxylic acid cycle (TCA) of aerobically respiring organisms. We describe the crystal structure of Escherichia coli E1o in its apo and holo forms at 2.6 A and 3.5 A resolution, respectively. The structures reveal the characteristic fold that binds thiamine diphosphate and resemble closely the alpha(2)beta(2) hetero-tetrameric E1 components of other 2-oxo acid dehydrogenase complexes, except that in E1o, the alpha and beta subunits are fused as a single polypeptide. The extended segment that links the alpha-like and beta-like domains forms a pocket occupied by AMP, which is recognised specifically. Also distinctive to E1o are N-terminal extensions to the core fold, and which may mediate interactions with other components of the 2-oxoglutarate dehydrogenase multienzyme complex. The active site pocket contains a group of three histidine residues and one serine that appear to confer substrate specificity and the capacity to accommodate the TCA metabolite oxaloacetate. Oxaloacetate inhibits E1o activity at physiological concentrations, and we suggest that the inhibition may allow coordinated activity within the TCA cycle. We discuss the implications for metabolic control in facultative anaerobes, and for energy homeostasis of the mammalian brain. PMID:17367808

Frank, René A W; Price, Amanda J; Northrop, Fred D; Perham, Richard N; Luisi, Ben F

2007-05-01

227

Repression of the interferon signal transduction pathway by the adenovirus E1A oncogene.  

PubMed Central

The signal transduction pathway initiated by type I interferon (alpha and beta interferons) is inhibited by expression of the adenovirus type 5 E1A oncogene. Cotransfection analyses with the E1A oncogene and an interferon-stimulated reporter gene show that mutations within an amino-terminal domain of the E1A oncoprotein are defective in transcriptional repression. Cotransfection experiments also revealed that the transcriptional repression is mediated through the interferon-stimulated response element (ISRE) found within the promoter of interferon-stimulated genes. Since interferon treatment activates a latent cytoplasmic DNA-binding factor that can recognize the ISRE and subsequently stimulate transcription, the appearance of this factor was analyzed in a cell line that constitutively expresses the E1A oncogene. The DNA binding activity of this transcriptional activator was found to be inhibited in the E1A-expressing cell line. In vitro cytoplasmic mixing experiments with extracts from control and E1A-expressing cells identified a specific component of this multimeric transcription factor to be defective. Images

Gutch, M J; Reich, N C

1991-01-01

228

A non-redundant function of cyclin E1 in hematopoietic stem cells  

PubMed Central

A precise balance between quiescence and proliferation is crucial for the lifelong function of hematopoietic stem cells (HSCs). Cyclins E1 and E2 regulate exit from quiescence in fibroblasts, but their role in HSCs remains unknown. Here, we report a non-redundant role for cyclin E1 in mouse HSCs. A long-term culture-initiating cell (LTC-IC) assay indicated that the loss of cyclin E1, but not E2, compromised the colony-forming activity of primitive hematopoietic progenitors. Ccne1?/? mice showed normal hematopoiesis in vivo under homeostatic conditions but a severe impairment following myeloablative stress induced by 5-fluorouracil (5-FU). Under these conditions, Ccne1?/? HSCs were less efficient in entering the cell cycle, resulting in decreased hematopoiesis and reduced survival of mutant mice upon weekly 5-FU treatment. The role of cyclin E1 in homeostatic conditions became apparent in aged mice, where HSC quiescence was increased in Ccne1?/? animals. On the other hand, loss of cyclin E1 provided HSCs with a competitive advantage in bone marrow serial transplantation assays, suggesting that a partial impairment of cell cycle entry may exert a protective role by preventing premature depletion of the HSC compartment. Our data support a role for cyclin E1 in controlling the exit from quiescence in HSCs. This activity, depending on the physiological context, can either jeopardize or protect the maintenance of hematopoiesis.

Campaner, Stefano; Viale, Andrea; De Fazio, Serena; Doni, Mirko; De Franco, Francesca; D'Artista, Luana; Sardella, Domenico; Pelicci, Pier Giuseppe; Amati, Bruno

2013-01-01

229

Identification and characterization of multiple conserved nuclear localization signals within adenovirus E1A.  

PubMed

The human adenovirus 5 (HAdV-5) E1A protein has a well defined canonical nuclear localization signal (NLS) located at its C-terminus. We used a genetic assay in the yeast Saccharomyces cerevisiae to demonstrate that the canonical NLS is present and functional in the E1A proteins of each of the six HAdV species. This assay also detects a previously described non-canonical NLS within conserved region 3 and a novel active NLS within the N-terminal/conserved region 1 portion of HAdV-5 E1A. These activities were also present in the E1A proteins of each of the other five HAdV species. These results demonstrate that, despite substantial differences in primary sequence, HAdV E1A proteins are remarkably consistent in that they contain one canonical and two non-canonical NLSs. By utilizing independent mechanisms, these multiple NLSs ensure nuclear localization of E1A in the infected cell. PMID:24725947

Marshall, Kris S; Cohen, Michael J; Fonseca, Greg J; Todorovic, Biljana; King, Cason R; Yousef, Ahmed F; Zhang, Zhiying; Mymryk, Joe S

2014-04-01

230

A non-redundant function of cyclin E1 in hematopoietic stem cells.  

PubMed

A precise balance between quiescence and proliferation is crucial for the lifelong function of hematopoietic stem cells (HSCs). Cyclins E1 and E2 regulate exit from quiescence in fibroblasts, but their role in HSCs remains unknown. Here, we report a non-redundant role for cyclin E1 in mouse HSCs. A long-term culture-initiating cell (LTC-IC) assay indicated that the loss of cyclin E1, but not E2, compromised the colony-forming activity of primitive hematopoietic progenitors. Ccne1(-/-) mice showed normal hematopoiesis in vivo under homeostatic conditions but a severe impairment following myeloablative stress induced by 5-fluorouracil (5-FU). Under these conditions, Ccne1(-/-) HSCs were less efficient in entering the cell cycle, resulting in decreased hematopoiesis and reduced survival of mutant mice upon weekly 5-FU treatment. The role of cyclin E1 in homeostatic conditions became apparent in aged mice, where HSC quiescence was increased in Ccne1(-/-) animals. On the other hand, loss of cyclin E1 provided HSCs with a competitive advantage in bone marrow serial transplantation assays, suggesting that a partial impairment of cell cycle entry may exert a protective role by preventing premature depletion of the HSC compartment. Our data support a role for cyclin E1 in controlling the exit from quiescence in HSCs. This activity, depending on the physiological context, can either jeopardize or protect the maintenance of hematopoiesis. PMID:24091730

Campaner, Stefano; Viale, Andrea; De Fazio, Serena; Doni, Mirko; De Franco, Francesca; D'Artista, Luana; Sardella, Domenico; Pelicci, Pier Giuseppe; Amati, Bruno

2013-12-01

231

ATF4 deficiency protects hepatocytes from oxidative stress via inhibiting CYP2E1 expression.  

PubMed

Activating transcription factor (ATF) 4 is involved in the regulation of oxidative stress in fibroblasts and neurons. The role of ATF4 in hepatocytes, however, is unknown. The aim of this study was to investigate the role of ATF4 in hepatocytes in oxidative stress under a high-fat diet (HFD). Here, we showed that palmitate-stimulated reactive oxygen species (ROS) production and triglyceride (TG) accumulation is blocked by ATF4 deficiency in primary hepatocytes. Consistently, HFD-induced oxidative stress, TG accumulation and expression of cytochrome P450, family 2, subfamily, polypeptide 1 (CYP2E1) are also blocked by knocking down ATF4 expression in the mouse liver. This suggests that ATF4 might regulate oxidative stress via CYP2E1 under an HFD. In addition, we observed that expression of CYP2E1 is indirectly regulated by ATF4 in a cAMP-responsive element binding protein (CREB)-dependent manner, which can directly activate the CYP2E1 promoter activity. Notably, ATF4-stimulated ROS production is inhibited in vivo by treatment with diallyl sulphide, a selective CYP2E1 inhibitor. Finally, we showed that ATF4 expression in the liver is responsible for the protective effects against HFD-induced CYP2E1 expression, oxidative stress, and TG accumulation. Taken together, these observations suggest that ATF4 is a novel regulator of oxidative stress as well as accumulation of TG in response to HFD. PMID:24373582

Wang, Chunxia; Li, Houkai; Meng, Qingshu; Du, Ying; Xiao, Fei; Zhang, Qian; Yu, Junjie; Li, Kai; Chen, Shanghai; Huang, Zhiying; Liu, Bin; Guo, Feifan

2014-01-01

232

Human ubiquitin-activating enzyme (E1): Compensation for heat-labile mouse E1 and its gene localization on the X chromosome  

Microsoft Academic Search

The authors have constructed interspecific somatic cell hybrids between a temperature-sensitive (ts) mutant cell line of mouse FM3A cells, ts85, that has a heat-labile ubiquitin-activating enzyme (E1) and a human diploid fibroblast cell line, IMR-90. A hybrid clone that could grow stably at a nonpermissive temperature (39C) was obtained. Segregation of the hybrid cells at a permissive temperature (33C) gave

Mami Kudo; Takemi Enomoto; M. Uf; Kaoru Sugasawa; Fumio Hanaoka; Takaaki Hori

1991-01-01

233

Combining strength and toughness in ultrahigh strength steel  

NASA Astrophysics Data System (ADS)

The main objective of this investigation is to examine the effects of a new technique, double-ageing, on the microstructure and mechanical properties of the ultrahigh strength steel Aermet 100. Under the condition of double-ageing, there is no apparent decrease in the steel strength. However, the impact fatigue life can be prolonged by 35.5% and the dynamic fracture toughness raised by 22.6% by this technique compared with normal ageing. Based on the observation of the microscopic structure, the physical mechanism of prolongation of fatigue life and enhancement of the stability of the reverted austenite is analysed further. The results show that this new technique is a breakthrough in optimally combining the strength and toughness of Aermet 100 steel. In light of the current understanding of this subject, the toughness of the reverted austenite formed at the time of heat preservation at the higher temperature of the double-ageing process increases drastically. Moreover, during the treatment at the lower temperature of the double-ageing process, the carbon separating from the martensitic ferrite of Aermet 100 steel will diffuse into the reverted austenite, resulting in a decrease of the brittleness of the martensite and an increase of the stability of the reverted austenite.

Wang, L. D.; Jiang, L. Z.; Zhu, M.; Liu, X.; Zhou, W. M.; Li, Y.

2004-08-01

234

CYP2E1 potentiates binge alcohol-induced gut leakiness, steatohepatitis, and apoptosis.  

PubMed

Ethanol-inducible cytochrome P450 2E1 (CYP2E1) contributes to increased oxidative stress and steatosis in chronic alcohol-exposure models. However, its role in binge ethanol-induced gut leakiness and hepatic injury is unclear. This study was aimed at investigating the role of CYP2E1 in binge alcohol-induced gut leakiness and the mechanisms of steatohepatitis. Female wild-type (WT) and Cyp2e1-null mice were treated with three doses of binge ethanol (WT-EtOH or Cyp2e1-null-EtOH) (6g/kg oral gavage at 12-h intervals) or dextrose (negative control). Intestinal histology of only WT-EtOH exhibited epithelial alteration and blebbing of lamina propria, and liver histology obtained at 6h after the last ethanol dose showed elevated steatosis with scattered inflammatory foci. These were accompanied by increased levels of serum endotoxin, hepatic enterobacteria, and triglycerides. All these changes, including the intestinal histology and hepatic apoptosis, determined by TUNEL assay, were significantly reversed when WT-EtOH mice were treated with the specific inhibitor of CYP2E1 chlormethiazole and the antioxidant N-acetylcysteine, both of which suppressed oxidative markers including intestinal CYP2E1. WT-EtOH also exhibited elevated amounts of serum TNF-?, hepatic cytokines, CYP2E1, and lipid peroxidation, with decreased levels of mitochondrial superoxide dismutase and suppressed aldehyde dehydrogenase 2 activity. Increased hepatocyte apoptosis with elevated levels of proapoptotic proteins and decreased levels of active (phosphorylated) p-AKT, p-AMPK, and peroxisome proliferator-activated receptor-?, all of which are involved in fat metabolism and inflammation, were observed in WT-EtOH. These changes were significantly attenuated in the corresponding Cyp2e1-null-EtOH mice. These data indicate that both intestinal and hepatic CYP2E1 induced by binge alcohol seems critical in binge alcohol-mediated increased nitroxidative stress, gut leakage, and endotoxemia; altered fat metabolism; and inflammation contributing to hepatic apoptosis and steatohepatitis. PMID:24064383

Abdelmegeed, Mohamed A; Banerjee, Atrayee; Jang, Sehwan; Yoo, Seong-Ho; Yun, Jun-Won; Gonzalez, Frank J; Keshavarzian, Ali; Song, Byoung-Joon

2013-12-01

235

Diabetes mellitus increases the in vivo activity of cytochrome P450 2E1 in humans  

PubMed Central

Aim Cytochrome P450 2E1 (CYP2E1) is thought to activate a number of protoxins, and has been implicated in the development of liver disease. Increased hepatic expression of CYP2E1 occurs in rat models of diabetes but it is unclear whether human diabetics display a similar up-regulation. This study was designed to test the hypothesis that human diabetics experience enhanced CYP2E1 expression. Methods The pharmacokinetics of a single dose of chlorzoxazone (500 mg), used as an index of hepatic CYP2E1 activity, was determined in healthy subjects (n = 10), volunteers with Type I (n = 13), and Type II (n = 8) diabetes mellitus. Chlorzoxazone and 6-hydroxychlorzoxazone in serum and urine were analysed by high-performance liquid chromatography. The expression of CYP2E1 mRNA in peripheral blood mononuclear cells was quantified by reverse transcriptase-polymerase chain reaction. Results The mean ± s.d. (90% confidence interval of the difference) chlorzoxazone area under the plasma concentration-time curve was significantly (P ? 0.05) reduced in obese Type II diabetics (15.7 ± 11.3 µg h ml?1; 9, 22) compared with healthy subjects (43.5 ± 16.9 µg h ml?1; 16, 40) and Type I diabetics (32.8 ± 9.2 µg h ml?1; 9, 25). There was a significant two-fold increase in the oral clearance of chlorzoxazone in obese Type II diabetics compared with healthy volunteers and Type I diabetics. The protein binding of chlorzoxazone was not significantly different between the three groups. In contrast, Type 1 diabetics and healthy volunteers demonstrated no difference in the oral clearance of chlorzoxazone. The urinary recovery of 6-hydroxychlorzoxazone as a percentage of the administered dose was not different between healthy, Type I and obese Type II diabetics. The elimination half-life of chlorzoxazone did not differ between the three groups. CYP2E1 mRNA was significantly elevated in Type I and obese Type II diabetics compared with healthy volunteers. The oral clearance of chlorzoxazone, elimination half-life, Tmax, and Cmax were not significantly influenced by weight, body mass index, serum glucose, serum cholesterol, or glycosylated haemoglobin. Conclusions There was a marked increase in hepatic CYP2E1 activity in obese Type II diabetics as assessed by chlorzoxazone disposition. Increased expression of CYP2E1 mRNA in peripheral blood mononuclear cells was found in both types of diabetes mellitus. Adverse hepatic events associated with Type II diabetes may be in part a result of enhanced CYP2E1 expression and activity.

Wang, Zaiqi; Hall, Stephen D; Maya, Juan F; Li, Lang; Asghar, Ali; Gorski, J C

2003-01-01

236

Epitope mapping of envelope glycoprotein E1 of hog cholera virus strain Brescia.  

PubMed

Four antigenic domains (A, B, C and D) on envelope glycoprotein E1 (gp51-54) of hog cholera virus strain Brescia have been specified by using 13 monoclonal antibodies (MAbs) that recognize non-conserved and conserved epitopes. It was shown that the non-conserved epitopes map to the N-terminal half of E1 by analysis of chimeric E1 proteins of strains Brescia and C. Conserved epitopes, however, could not be mapped using this approach. Here we describe mapping of both conserved and non-conserved epitopes on E1 by the use of an extensive set of single and double deletion mutants of E1 of strain Brescia. Deletion mutants were transiently expressed in COS1 cells and analysed by immunostaining with the 13 MAbs directed against strain Brescia and four MAbs directed against strain C. All MAbs bound to the N-terminal half of E1, i.e. amino acids 690 to 866 encoded by the sequence of strain Brescia. Domain B and one epitope in domain C are located between residues 690 and 773. Other epitopes in domain C are located on an extended region, i.e. between residues 690 and 800. Conserved epitopes of domain A are mapped between residues 766 and 866, whereas the only non-conserved epitope in this domain is located between residues 766 and 813. Domain D, represented by one MAb, is located in the same region as this non-conserved epitope of domain A, i.e. between residues 766 and 800. The results suggest the presence of two distinct antigenic units on E1, one consisting of domains B and C and the other consisting of domain A. PMID:7691986

van Rijn, P A; van Gennip, H G; de Meijer, E J; Moormann, R J

1993-10-01

237

Expression of Estrogen Sulfotransferase 1E1 and Steroid Sulfatase in Breast Cancer: A Immunohistochemical Study  

PubMed Central

It is known that the steroid sulfatase (STS) and the estrogen sulfotransferase (EST1E1) are commonly expressed in human breast carcinomas. STS and EST1E1 combined action could maintain the equilibrium between sulfated (inactive) and unconjugated (active) estrogens, which might have effects on development of hormone dependent breast cancer. We studied the expression of the STS and EST1E1 in 88 breast carcinomas and 57 adjacent non-malignant tissues by immunohistochemistry. The results were correlated with the tumor expression of estrogen receptor ? (ER-?) and ? (ER-?), progesterone receptor A (PR-A) and B (PR-B) and the proliferation marker CDC47, the tumoral type and stage and the age at surgery. STS expression was higher in carcinoma specimens than in adjacent normal tissues, although not to a significant level (p = 0.064) and it was positively associated with CDC47 expression (p < 0.05). These observations support the hypothesis that STS is overexpressed in breast cancer and associated with a worse prognosis. EST1E1 was observed for the first time in the nuclei of epithelial and tumoral cells. Tumor expression of EST1E1 was positively correlated with ER-? (p < 0.01) and PR-B (p < 0.05), two steroid receptors already associated with an improve prognosis for breast cancer. Controlling the STS overexpression in carcinomas could be a way to inhibit cancer growth. The significance of the association between EST1E1 and ER-? or PR-B should be further studied since these two receptors are transcription activators and may regulate the expression of protective enzymes like EST1E1.

Poisson Pare, D.; Song, D.; Luu-The, V.; Han, B.; Li, S.; Liu, G.; Labrie, F; Pelletier, G.

2009-01-01

238

In vivo and in vitro characterization of CYP2E1 activity in Japanese and Caucasians.  

PubMed

Chlorzoxazone's disposition after oral administration was determined in 20 young healthy Caucasian men and a similar group of Japanese men. The drug's plasma concentrations were significantly higher and its rate of elimination slower in Japanese compared to Caucasian men. Accordingly, chlorzoxazone's oral clearance was smaller (40%) in Japanese men and a similar difference (30%) was still apparent after normalizing for body weight (3.74 +/- 1.23 versus 5.05 +/- 1.41 ml.min-1.kg-1, P < .05). This slower elimination was associated with a reduced (fractional) clearance by 6-hydroxylation (2.34 +/- 1.04 ml.min-1.kg-1 versus 3.23 +/- 1.10, P < .05). Because such metabolism is mediated by cytochrome P4502E1 (CYP2E1), these findings suggest a lower level of the enzyme's catalytic activity in Japanese men. This was confirmed by in vitro studies with microsomes prepared from livers of individuals representative of the two racial groups. CYP2E1 levels were lower (61% P < .002) and CYP2E1-mediated chlorzoxazone 6-hydroxylase (22%, P < .001) and aniline 4-hydroylase (35%, P < .0001) activities were reduced in Japanese preparations compared to those from Caucasians. No relationships were found between measures of CYP2E1 activity, both in vivo and in vitro, and genomic polymorphisms in the CYP2E1 gene identified by Rsal/Pstl and Dral restriction fragment length polymorphisms. Collectively, these data show an interracial difference in CYP2E1 activity. Because this enzyme is importantly involved in the activation of environmental procarcinogens, such a difference may account, in part, for the lower rate of some cancers, e.g., lung cancer, in Japanese compared to Caucasians men. PMID:8858968

Kim, R B; Yamazaki, H; Chiba, K; O'Shea, D; Mimura, M; Guengerich, F P; Ishizaki, T; Shimada, T; Wilkinson, G R

1996-10-01

239

Calculated strength of irradiated ferritics  

NASA Astrophysics Data System (ADS)

Effects of irradiation on dislocation recovery kinetics and strengthening have been calculated and compared to reported responses in Fe-2 14Cr-lMo steels. The analysis indicates that predicted interstitial loop growth causes increases in strength at 673 K that are comparable to measure increases in strength at 10 dpa. With increasing temperature, radiation softening was predicted as expected from experimental observations. The transition from hardening to softening was predicted to occur at temperatures about 50 K above the measured transition. A strong hardening effect was predicted from depleted zone accumulation at 673 K, but only when depleted zones were assumed to be unbiased microvoids. Radiation enhanced growth of Mo 2C precipitates were predicted to have an influence on hardening that was less than predicted for hardening caused by loop growth. At later stages of carbide evolution, irradiation softening may occur because of reduction in solid solution hardening and enhancement in carbide coarsening.

Simonen, E. P.

1985-08-01

240

Extra ?-ray strength for 116,117Sn arising from pygmy dipole resonance  

NASA Astrophysics Data System (ADS)

Photoneutron cross sections were measured for 117Sn and 116Sn near neutron thresholds with quasi-monochromatic laser Compton scattering ?-rays. The measured cross sections for 117Sn and 116Sn are strongly enhanced from the threshold behavior expected for L = 1 neutron emissions after E1 photoexcitation. This suggests the presence of extra ?-ray strength in the low-energy tail of the giant dipole resonance. The present cross sections were analyzed together with radiative neutron capture cross sections for 116Sn within the framework of the statistical model calculation. It is shown that the extra ?-ray strength can be interpreted as pygmy E1 resonance which was previously reported in the nuclear resonance fluorescence experiment for 116Sn and 124Sn.

Kamata, M.; Utsunomiya, H.; Akimune, H.; Yamagata, T.; Itoh, O.; Iwamoto, C.; Kondo, T.; Toyokawa, H.; Lui, Y.-W.; Goriely, S.

2010-06-01

241

Trefilov and strength physics today  

Microsoft Academic Search

The paper discusses the main topics of the plenary report given at the 49th International Conference “Relevant Problems of Strength” (Kiev, June 14–17, 2010) dedicated to the 80th anniversary of Academician Trefilov’s birth. Special attention is paid to strengthening in transition from micro- to nanosizes.\\u000a It is shown that S-functions can be used to obtain a generalized equation for the

S. A. Firstov

2010-01-01

242

Physical Strength and Job Performance  

NSDL National Science Digital Library

Created by David Lane of Rice University, this case study aims to answer the question, "How does one select employees to perform physically demanding jobs?" It examines the relationship between isometric strength tests and job performance for one hundred forty-seven workers. The author has structured the lesson to provide a background, methods and procedures, univariate statistics, scatter plots, correlations, regression and raw data. Some of the main concepts include: correlation, linear regression, multiple regression.

Lane, David M.

2009-03-03

243

An Interlaminar Tensile Strength Specimen  

NASA Technical Reports Server (NTRS)

This paper describes a technique to determine interlaminar tensile strength, sigma(sub 3c), of a fiber reinforced composite material using a curved beam. The specimen was a unidirectional curved beam, bent 90 deg, with straight arms. Attached to each arm was a hinged loading mechanism that was held by the grips of a tension testing machine. Geometry effects of the specimen, including the effects of loading arm length, inner radius, thickness, and width, were studied. The data sets fell into two categories: low strength corresponding to a macroscopic flaw related failure and high strength corresponding to a microscopic flaw related failure. From the data available, the specimen width and loading arm length had little effect on sigma(sub 3c). The inner radius was not expected to have a significant effect on sigma(sub 3c), but this conclusion could not be confirmed because of differences in laminate quality for each curve geometry. The thicker specimens had the lowest value of sigma(sub 3c) because of poor laminate quality.

Martin, Roderick H.; Jackson, Wade C.

1993-01-01

244

Strength Scaling in Fiber Composites  

NASA Technical Reports Server (NTRS)

A research program was initiated to study and isolate the factors responsible for scale effects in the tensile strength of graphite/epoxy composite laminates. Four layups were chosen with appropriate stacking sequences so as to highlight individual and interacting failure modes. Four scale sizes were selected for investigation including full scale size, 3/4, 2/4, and 1/4, with n = to 4, 3, 2, and 1, respectively. The full scale specimen sizes was 32 piles thick as compared to 24, 16, and 8 piles for the 3/4, 2/4, and 1/4 specimen sizes respectively. Results were obtained in the form of tensile strength, stress-strain curves and damage development. Problems associated with strength degradation with increasing specimen sizes are isolated and discussed. Inconsistencies associated with strain measurements were also identified. Enhanced x ray radiography was employed for damage evaluation, following step loading. It was shown that fiber dominated layups were less sensitive to scaling effects compared to the matrix dominated layups.

Kellas, Sotiris; Morton, John

1990-01-01

245

Antigenic structure of envelope glycoprotein E1 of hog cholera virus.  

PubMed

Envelope glycoprotein E1 (gp51 to gp54) is the most antigenic protein of hog cholera virus or classical swine fever virus (CSFV). Four antigenic domains, A to D, have been mapped on E1 with a panel of monoclonal antibodies (MAbs) raised against CSFV strain Brescia. The boundaries of these domains have been established by extensive studies on binding of MAbs to transiently expressed deletion mutants of E1 (P. A. van Rijn, E. J. de Meijer, H. G. P. van Gennip, and R. J. M. Moormann, J. Gen. Virol. 74:2053-2060, 1993). In this study, we used neutralizing MAbs of domains A, B, and C to isolate MAb-resistant mutants (MAR mutants) of CSFV strain Brescia and Chinese vaccine strain ("C"). The E1 genes of MAR mutants were cloned in a eukaryotic expression vector, and the effects of MAR mutations on epitopes were studied with a panel of 19 MAbs by immunostaining of COS1 cells transiently expressing these mutant E1s. Except for the MAR mutation Cys-->Arg at position 792, which abolished binding of all MAbs of domains A and D, amino acid substitutions affected only MAbs belonging to the same domain as the MAb used to select the MAR mutant. However, a MAR mutation in a particular domain did not per se abolish binding of all MAbs recognizing that domain. Furthermore, MAR mutants possessed conservative as well as nonconservative amino acid substitutions. To investigate the significance of a secondary structure for the binding of MAbs, all cysteine residues in the N-terminal antigenic part of E1 were mutated to serine. We found that the cysteines at positions 693 and 737 were essential for binding by MAbs of domains B and C, whereas those at positions 792, 818, 828, and 856 appeared to be essential for the binding of most MAbs of domains A and D. These results fully comply with the previously proposed two-unit structure of the N-terminal half of E1. One unit consists of antigenic domains B and C, whereas the other unit consists of the highly conserved domain A and domain D. We conclude that the first six cysteines are critical for the correct folding of E1. A model of the antigenic structure of E1 is presented and discussed. PMID:7514680

van Rijn, P A; Miedema, G K; Wensvoort, G; van Gennip, H G; Moormann, R J

1994-06-01

246

Resolvin E1 reduces hepatic fibrosis in mice with Schistosoma japonicum infection  

PubMed Central

The aim of this study was to investigate whether resolvin E1 (RvE1) protects against hepatic fibrosis in a murine model of liver fibrosis induced by Schistosoma japonicum infection. A total of 30 pathogen-free Kunming mice were randomly and equally divided into three groups: Control (uninfected, untreated), model (infected, untreated) and RvE1 intervention (infected, RvE1-treated; 100 ng daily). The mice were infected with Schistosoma japonicum by inoculating the abdominal skin with 20±2 cercariae to induce models of liver fibrosis. The area and numbers of the granulomas in the livers were assessed through histopathology after 70 days of treatment. The levels of tumor necrosis factor (TNF)-? and interferon (IFN)-? were evaluated in the serum by enzyme-linked immunosorbent assay (ELISA). The expression levels of TNF-? were detected in the hepatic tissue by reverse transcription-polymerase chain reaction and western blot analysis. The activity levels of alanine aminotransferase and aspartate aminotransferase were determined in the serum by ELISA. The expression levels of laminin (LN), hyaluronic acid (HA), procollagen type III (PC-III) and type IV collagen (IV-C) were detected in the serum by radioimmunoassays. The results revealed that the mean area of the granulomas was smaller in the RvE1 intervention group compared with that in the model group. Following RvE1 treatment, the serum levels of TNF-? were lower than those in the model group, while the serum levels of IFN-? were higher compared with those in the model group. The expression levels of TNF-? were lower in the hepatic tissue following RvE1 treatment compared with those in the model group. The indicators of liver fibrosis, the levels of LN, HA, PC-III and IV-C in the serum, were lower following RvE1 treatment than those in the model group. In conclusion, RvE1 treatment may reduce the growth of granulomas, thereby slowing the process of hepatic fibrosis, and this effect may be the result of anti-inflammatory and immune system adjustment.

QIU, WENHONG; GUO, KAIWEN; YI, LUYANG; GONG, YELI; HUANG, LIXIA; ZHONG, WEI

2014-01-01

247

Circulating viral core and E1 antigen levels as supplemental markers for HCV chronic hepatitis.  

PubMed

The performance of polyclonal monospecific rabbit anti-sera raised against synthetic peptides derived from conserved HCV sequences of genotype 4 was evaluated for efficient detection of viral core and E1 antigens in circulating immune complexes (ICs) precipitated from 65 serum samples of HCV patients. The infection was established in those patients by the presence of HCV RNA in their sera. A novel enzyme-linked immunosorbent assay (ELISA) was developed for the detection of HCV core and E1 antigen in serum samples. Western blot analyses were used to demonstrate the presence of the core and E1 target antigen in serum samples. The mean OD readings of both core and E1 antigens were significantly higher (P < 0.05) among the viremic patients when compared to controls. Also a significant positive correlation (P < 0.05, r = 0.98) between the values of both core and E1 was recorded. Western blot analysis based on monospecific antibodies against core and E1 recognized the 38-kDa and 88 -kDa bands respectively in the sera of all infected patients. No specific reaction was observed with the sera from uninfected individuals. Interestingly the results of core and E1 antigen levels displayed no positive correlation with the HCV copy number as measured by bDNA. Liver enzymes (ALT and AST) showed a moderate positive correlation (r = 0.44 and 0.47 respectively) with the viral core antigens level. The same trend holds true for E1 (r = 0.43 and 0.64 for ALT and AST respectively). HCV load in infected patients revealed extremely poor correlation with serum ALT and AST levels (r = 0.022 and 0.002 respectively). In conclusion we present a new combination of serological tools correlating with liver enzyme levels that could be utilized as supplemental tests to viral load testing. Also, a sensitive and specific immunoassay was developed for the detection of HCV core and E1 in human serum. This test can be applied for laboratory diagnosis of HCV infection. PMID:16948845

El Awady, Mostafa K; El Abd, Yasmine S; Shoeb, Hussein A; Tabll, Ashraf A; Hosny, Alaa El Din M S; El Shenawy, Reem M; Atef, Khaled; Bader El Din, Noha G; Bahgat, Mahmoud M

2006-01-01

248

Investigation of Indazole Unbinding Pathways in CYP2E1 by Molecular Dynamics Simulations  

PubMed Central

Human microsomal cytochrome P450 2E1 (CYP2E1) can oxidize not only low molecular weight xenobiotic compounds such as ethanol, but also many endogenous fatty acids. The crystal structure of CYP2E1 in complex with indazole reveals that the active site is deeply buried into the protein center. Thus, the unbinding pathways and associated unbinding mechanisms remain elusive. In this study, random acceleration molecular dynamics simulations combined with steered molecular dynamics and potential of mean force calculations were performed to identify the possible unbinding pathways in CYP2E1. The results show that channel 2c and 2a are most likely the unbinding channels of CYP2E1. The former channel is located between helices G and I and the B-C loop, and the latter resides between the region formed by the F-G loop, the B-C loop and the ?1 sheet. Phe298 and Phe478 act as the gate keeper during indazole unbinding along channel 2c and 2a, respectively. Previous site-directed mutagenesis experiments also supported these findings.

Shen, Zhonghua; Cheng, Feixiong; Xu, You; Fu, Jing; Xiao, Wen; Shen, Jie; Liu, Guixia; Li, Weihua; Tang, Yun

2012-01-01

249

Identifying New Mascons of Moon Using Updated Chang'E-1 Lunar Topography and Gravity Models  

NASA Astrophysics Data System (ADS)

Chinese 1st lunar orbiter Chang'E-1 is playing an important role in selenodetic explorations, by means of modeling topography with laser ranging as well as of improving gravity field model with radio matric tracking data. After carefully checking and validating the laser and tracking data of Chang'E-1 mission, new topography and gravity model have been estimated. The errors due to time tag, instrumental bias, and S/C orbits in LAM data are removed for new topography model. The new gravity model using Chang'E-1 data can success state of art lunar gravity model at long wave length with a factor of two. Also, using the new developed lunar topography model and gravity model of Chang'E -1, some middle scare surface characteristics and old mascon basins and craters have been newly identified and discovered.[This work is supported by Chang'E-1 mission, by NSFC No.10973031 as well as by China national high-tech projects 2010AA122206

Ping, J.; Huang, Q.; Su, X.; Jianguo, Y.

2011-12-01

250

Active site remodeling accompanies thioester bond formation in the SUMO E1  

PubMed Central

E1 enzymes activate ubiquitin (Ub) and ubiquitin-like (Ubl) proteins in two steps by carboxy-terminal adenylation and thioester bond formation to a conserved catalytic cysteine in the E1 Cys domain. The structural basis for these intermediates remains unknown. Here we report crystal structures for human SUMO E1 in complex with SUMO adenylate and tetrahedral intermediate analogs at 2.45 Å and 2.6 Å, respectively. These structures show that side chain contacts to ATP·Mg are released after adenylation to facilitate a 130 degree rotation of the Cys domain during thioester bond formation that is accompanied by remodeling of key structural elements including the helix that contains the E1 catalytic cysteine, the cross-over and re-entry loops, and refolding of two helices that are required for adenylation. These changes displace side chains required for adenylation with side chains required for thioester bond formation. Mutational and biochemical analyses suggest these mechanisms are conserved in other E1s.

Olsen, Shaun K.; Capili, Allan D.; Lu, Xuequan; Tan, Derek S.; Lima, Christopher D.

2009-01-01

251

Active site remodelling accompanies thioester bond formation in the SUMO E1  

SciTech Connect

E1 enzymes activate ubiquitin (Ub) and ubiquitin-like (Ubl) proteins in two steps by carboxy-terminal adenylation and thioester bond formation to a conserved catalytic cysteine in the E1 Cys domain. The structural basis for these intermediates remains unknown. Here we report crystal structures for human SUMO E1 in complex with SUMO adenylate and tetrahedral intermediate analogues at 2.45 and 2.6 {angstrom}, respectively. These structures show that side chain contacts to ATP-Mg are released after adenylation to facilitate a 130 degree rotation of the Cys domain during thioester bond formation that is accompanied by remodelling of key structural elements including the helix that contains the E1 catalytic cysteine, the crossover and re-entry loops, and refolding of two helices that are required for adenylation. These changes displace side chains required for adenylation with side chains required for thioester bond formation. Mutational and biochemical analyses indicate these mechanisms are conserved in other E1s.

Olsen, Shaun K.; Capili, Allan D.; Lu, Xuequan; Tan, Derek S.; Lima, Christopher D. (SKI)

2010-03-30

252

Expression and Characterization of Acidothermus celluloyticus E1 Endoglucanase in Transgenic Duckweed Lemna minor 8627  

SciTech Connect

Endoglucanase E1 from Acidothermus cellulolyticus was expressed cytosolically under control of the cauliflower mosaic virus 35S promoter in transgenic duckweed, Lemna minor 8627 without any obvious observable phenotypic effects on morphology or rate of growth. The recombinant enzyme co-migrated with the purified catalytic domain fraction of the native E1 protein on western blot analysis, revealing that the cellulose-binding domain was cleaved near or in the linker region. The duckweed-expressed enzyme was biologically active and the expression level was up to 0.24% of total soluble protein. The endoglucanase activity with carboxymethylcellulose averaged 0.2 units mg protein{sup -1} extracted from fresh duckweed. The optimal temperature and pH for E1 enzyme activity were about 80 C and pH 5, respectively. While extraction with HEPES (N-[2-hydroxyethyl]piperazine-N{prime}-[2-ethanesulfonic acid]) buffer (pH 8) resulted in the highest recovery of total soluble proteins and E1 enzyme, extraction with citrate buffer (pH 4.8) at 65 C enriched relative amounts of E1 enzyme in the extract. This study demonstrates that duckweed may offer new options for the expression of cellulolytic enzymes in transgenic plants.

Sun, Y.; Cheng, J. J.; Himmel, M. E.; Skory, C. D.; Adney, W. S.; Thomas, S. R.; Tisserat, B.; Nishimura, Y.; Yamamoto, Y. T.

2007-01-01

253

Cross-Inhibition of Chikungunya Virus Fusion and Infection by Alphavirus E1 Domain III Proteins  

PubMed Central

Alphaviruses are small enveloped RNA viruses that include important emerging human pathogens, such as chikungunya virus (CHIKV). These viruses infect cells via a low-pH-triggered membrane fusion reaction, making this step a potential target for antiviral therapies. The E1 fusion protein inserts into the target membrane, trimerizes, and refolds to a hairpin-like conformation in which the combination of E1 domain III (DIII) and the stem region (DIII-stem) pack against a core trimer composed of E1 domains I and II (DI/II). Addition of exogenous DIII proteins from Semliki Forest virus (SFV) has been shown to inhibit E1 hairpin formation and SFV fusion and infection. Here we produced and characterized DIII and DI/II proteins from CHIKV and SFV. Unlike SFV DIII, both core trimer binding and fusion inhibition by CHIKV DIII required the stem region. CHIKV DIII-stem and SFV DIII-stem showed efficient cross-inhibition of SFV, Sindbis virus, and CHIKV infections. We developed a fluorescence anisotropy-based assay for the binding of SFV DIII-stem to the core trimer and used it to demonstrate the relatively high affinity of this interaction (Kd [dissociation constant], ?85 nM) and the importance of the stem region. Together, our results support the conserved nature of the key contacts of DIII-stem in the alphavirus E1 homotrimer and describe a sensitive and quantitative in vitro assay for this step in fusion protein refolding.

Sanchez-San Martin, Claudia; Nanda, Soumya; Zheng, Yan; Fields, Whitney

2013-01-01

254

Rb function is required for E1A-induced S-phase checkpoint activation.  

PubMed

It is widely accepted that adenoviral E1A exerts its influence on recipient cells through binding to the retinoblastoma (Rb) family proteins, followed by a global release of E2F factors from pocket-protein control. Our study challenges this simple paradigm by demonstrating previously unappreciated complexity. We show that E1A-expressing primary and transformed cells are characterized by the persistence of Rb-E2F1 complexes. We provide evidence that E1A causes Rb stabilization by interfering with its proteasomal degradation. Functional experiments supported by biochemical data reveal not only a dramatic increase in Rb and E2F1 protein levels in E1A-expressing cells but also demonstrate their activation throughout the cell cycle. We further show that E1A activates an Rb- and E2F1-dependent S-phase checkpoint that attenuates the growth of cells that became hyperploid through errors in mitosis and supports the fidelity DNA replication even in the absence of E2F complexes with other Rb family proteins, thereby functionally substituting for the loss of p53. Our results support the essential role of Rb and E2F1 in the regulation of genomic stability and DNA damage checkpoints. PMID:18451867

Nemajerova, A; Talos, F; Moll, U M; Petrenko, O

2008-09-01

255

Olive cultivar origin is a major cause of polymorphism for Ole e 1 pollen allergen  

PubMed Central

Background Pollens from different olive (Olea europaea L.) cultivars have been shown to differ significantly in their content in Ole e 1 and in their overall allergenicity. This allergen is, in addition, characterized by a high degree of polymorphism in its sequence. The purpose of this study is to evaluate the putative presence of divergences in Ole e 1 sequences from different olive cultivars. Results RNA from pollen individually collected from 10 olive cultivars was used to amplify Ole e 1 sequences by RT-PCR, and the sequences were analyzed by using different bioinformatics tools. Numerous nucleotide substitutions were detected throughout the sequences, many of which resulted in amino acid substitutions in the deduced protein sequences. In most cases variability within a single variety was much lower than among varieties. Key amino acid changes in comparison with "canonical" sequences previously described in the literature included: a) the substitution of C19-relevant to the disulphide bond structure of the protein-, b) the presence of an additional N-glycosylation motif, and c) point substitutions affecting regions of Ole e 1 already described like relevant for the immunogenicity/allergenicity of the protein. Conclusion Varietal origin of olive pollen is a major factor determining the diversity of Ole e 1 variants. We consider this information of capital importance for the optimal design of efficient and safe allergen formulations, and useful for the genetic engineering of modified forms of the allergen among other applications.

Hamman-Khalifa, AbdelMounim; Castro, Antonio Jesus; Jimenez-Lopez, Jose Carlos; Rodriguez-Garcia, Maria Isabel; Alche, Juan de Dios

2008-01-01

256

Genetic mapping of a major site of phosphorylation in adenovirus type 2 E1A proteins  

SciTech Connect

Adenovirus early region 1A (E1A) encodes two acidic phosphoproteins which are required for transactivation of viral transcription, efficient viral DNA replication in phase G/sub 0/-arrested human cells, and oncogenic transformation of rodent cells. Biochemical analysis of in vivo /sup 32/P-labeled adenovirus type 2 E1A proteins purified with monoclonal antibodies demonstrated that these proteins were phosphorylated at multiple serine residues. Two-dimensional phosphotryptic peptide maps of wild-type and mutant E1A proteins were used to locate a major site of E1A protein phosphorylation at serine-219 of the large E1A protein. Although this serine fell within a consensus sequence for phosphorylation by the cyclic AMP-dependent protein kinases, experiments with mutant CHO cells defective in these enzymes indicated that it was not. Oligonucleotide-directed mutagenesis was used to substitute an alanine for serine-219. This mutation prevented phosphorylation at this site. Nonetheless, the mutant was indistinguishable from the wild type for early gene transactivation, replication on G/sub 0/-arrested WI-38 cells, and transformation of cloned rat embryo fibroblast cells.

Tsukamotot, A.S.; Ponticelli, A.; Berk, A.J.; Gaynor, R.B.

1986-07-01

257

Cooperative effects for CYP2E1 differ between styrene and its metabolites.  

PubMed

Cooperative interactions are frequently observed in the metabolism of drugs and pollutants by cytochrome P450s; nevertheless, the molecular determinants for cooperativity remain elusive. Previously, we demonstrated that steady-state styrene metabolism by CYP2E1 exhibits positive cooperativity. We hypothesized that styrene metabolites have lower affinity than styrene toward CYP2E1 and limited ability to induce cooperative effects during metabolism. To test the hypothesis, we determined the potency and mechanism of inhibition for styrene and its metabolites toward oxidation of 4-nitrophenol using CYP2E1 Supersomes® and human liver microsomes. Styrene inhibited the reaction through a mixed cooperative mechanism with high affinity for the catalytic site (67?µM) and lower affinity for the cooperative site (1100?µM), while increasing substrate turnover at high concentrations. Styrene oxide and 4-vinylphenol possessed similar affinity for CYP2E1. Styrene oxide behaved cooperatively like styrene, but 4-vinylphenol decreased turnover at high concentrations. Styrene glycol was a very poor competitive inhibitor. Among all compounds, there was a positive correlation with binding and hydrophobicity. Taken together, these findings for CYP2E1 further validate contributions of cooperative mechanisms to metabolic processes, demonstrate the role of molecular structure on those mechanisms and underscore the potential for heterotropic cooperative effects between different compounds. PMID:23327532

Hartman, Jessica H; Boysen, Gunnar; Miller, Grover P

2013-09-01

258

Cooperative effects for CYP2E1 differ between styrene and its metabolites  

PubMed Central

Cooperative interactions are frequently observed in the metabolism of drugs and pollutants by cytochrome P450s; nevertheless, the molecular determinants for cooperativity remain elusive. Previously, we demonstrated that steady-state styrene metabolism by CYP2E1 exhibits positive cooperativity.We hypothesized that styrene metabolites have lower affinity than styrene toward CYP2E1 and limited ability to induce cooperative effects during metabolism. To test the hypothesis, we determined the potency and mechanism of inhibition for styrene and its metabolites toward oxidation of 4-nitrophenol using CYP2E1 Supersomes® and human liver microsomes.Styrene inhibited the reaction through a mixed cooperative mechanism with high affinity for the catalytic site (67 ?M) and lower affinity for the cooperative site (1100 ?M), while increasing substrate turnover at high concentrations. Styrene oxide and 4-vinylphenol possessed similar affinity for CYP2E1. Styrene oxide behaved cooperatively like styrene, but 4-vinylphenol decreased turnover at high concentrations. Styrene glycol was a very poor competitive inhibitor. Among all compounds, there was a positive correlation with binding and hydrophobicity.Taken together, these findings for CYP2E1 further validate contributions of cooperative mechanisms to metabolic processes, demonstrate the role of molecular structure on those mechanisms and underscore the potential for heterotropic cooperative effects between different compounds.

Hartman, Jessica H.; Boysen, Gunnar; Miller, Grover P.

2014-01-01

259

Strength loss in kraft pulping  

NASA Astrophysics Data System (ADS)

Unbleached kraft pulps from two U.S. mills were 21% and 26% weaker than comparable laboratory pulps from the same chip sources, when assessed as the tear index at a tensile index of 70 kN.m/kg. The phenomena involved were clarified by characterizing the differences between the mill and laboratory pulps in terms of fundamental fiber properties. All of the strength loss could be explained by a reduction in intrinsic fiber strength of 9% to 11%, as estimated from wet zero-span tensile tests and fiber length distributions. Most of the effects of different fiber shape and length were isolated by PFI mill refining and decrilling, respectively. The higher fiber coarseness of mill pulps was a factor in their maximum density and bond strength, but changes in these variables were analogous to those of laboratory pups due to similar swelling. Specific bond strength, determined from a wet pressing experiment, was similar in mill and laboratory pulps. Neither carbohydrate composition nor crystalline structure, assessed through x-ray diffraction analysis, were significant factors in the observed fiber strength differences. The mill pulps were not more heterogeneous than the laboratory pulps, within the resolution of a fractionation experiment. The number of weak points in each pulp was assessed through analysis of the amount of fiber cutting during PFI mill refining and treatments with potassium superoxide or cellulase. The results suggested that the chemistry of kraft pulping preferentially weaken short, slender fibers, while mechanical stresses during the hot discharge of batch digesters mainly affect long, thick fibers. The greater number of weak points in the long-fiber fractions of mill pulps is probably associated with their lower wet zero-span tensile indices. Automated optical detection of major singularities with a prototype instrument suggested that only the weak points induced by mechanical stress could be detected by local variations in birefringence. In contrast, chemically damaged short, slender fibers were not optically active. Strong chemical attack during superoxide treatment appeared to affect all fibers, but the effect of fiber cutting was partially offset by a preferential dissolution of short fibers and fines. A simple model of weak point formation by combinations of mechanical stress and localized chemical attack was sufficient to explain all the experimental results.

Iribarne, Jose

260

[The compressive strength, tensile strength, flexural strength and micro-hardness of Plat-II Castable Ceramics].  

PubMed

In preparation for the clinical use of Plat-II Castable Ceramics (PCC-II), we tested its compressive strength, tensile strength, flexural strength and microhardness. The flexural strength was tested by the three-point bending test. The result showed that the compressive strength was 541.7 MPa; the tensile strength 42.5 MPa; the flexural strength 142.0 MPa; the modulus of elasticity 61.4 GPa; and the micro-hardness 499.6 kg/mm3. The strength anol micro-hardness of PCC-II materials were better than those of human enamel. So PCC-II is applicable to restorations in dentistry. PMID:10683943

Wang, H; Zhao, Y; Fan, Y; Chen, Y

1997-12-01

261

Double ion beams and accelerated ions observed by SWIDs on Chang'E-1  

NASA Astrophysics Data System (ADS)

Chang'E-1 is the first Chinese lunar exploration spacecraft launced in 2007. Solar Wind Ion Detectors(SWIDs) are two scientific instruments on Chang'E-1 to measure the solar wind and the plasma environment around the Moon. Some cases of double ion beams in solar wind were observed by SWIDs. These double ion beams present double proton beams with a single alpha beam. Another insteresting phenomenon observed by SWIDs is the accelerated ions when the spacecraft was over the magnetic anomalies. The magnetic anomaly may induce mini-magnetosphere, which was confirmed both by simulation and measurement of some other lunar exploration spacecrafts. The accelerated ions observed by Chang'E-1 may be the result of the interaction of the solar wind and the mini-magnetosphere of the Moon.

Kong, Linggao; Zhang, Aibing; Wang, Shijin

2012-07-01

262

Cytochrome P450 2E1 potentiates ethanol induction of hypoxia and HIF-1? in vivo.  

PubMed

Ethanol induces hypoxia and elevates HIF-1? in the liver. CYP2E1 plays a role in the mechanisms by which ethanol generates oxidative stress, fatty liver, and liver injury. This study evaluated whether CYP2E1 contributes to ethanol-induced hypoxia and activation of HIF-1? in vivo and whether HIF-1? protects against or promotes CYP2E1-dependent toxicity in vitro. Wild-type (WT), CYP2E1-knock-in (KI), and CYP2E1 knockout (KO) mice were fed ethanol chronically; pair-fed controls received isocaloric dextrose. Ethanol produced liver injury in the KI mice to a much greater extent than in the WT and KO mice. Protein levels of HIF-1? and downstream targets of HIF-1? activation were elevated in the ethanol-fed KI mice compared to the WT and KO mice. Levels of HIF prolyl hydroxylase 2, which promotes HIF-1? degradation, were decreased in the ethanol-fed KI mice in association with the increases in HIF-1?. Hypoxia occurred in the ethanol-fed CYP2E1 KI mice as shown by an increased area of staining using the hypoxia-specific marker pimonidazole. Hypoxia was lower in the ethanol-fed WT mice and lowest in the ethanol-fed KO mice and all the dextrose-fed mice. In situ double staining showed that pimonidazole and CYP2E1 were colocalized to the same area of injury in the hepatic centrilobule. Increased protein levels of HIF-1? were also found after acute ethanol treatment of KI mice. Treatment of HepG2 E47 cells, which express CYP2E1, with ethanol plus arachidonic acid (AA) or ethanol plus buthionine sulfoximine (BSO), which depletes glutathione, caused loss of cell viability to a greater extent than in HepG2 C34 cells, which do not express CYP2E1. These treatments elevated protein levels of HIF-1? to a greater extent in E47 cells than in C34 cells. 2-Methoxyestradiol, an inhibitor of HIF-1?, blunted the toxic effects of ethanol plus AA and ethanol plus BSO in the E47 cells in association with inhibition of HIF-1?. The HIF-1? inhibitor also blocked the elevated oxidative stress produced by ethanol/AA or ethanol/BSO in the E47 cells. These results suggest that CYP2E1 plays a role in ethanol-induced hypoxia, oxidative stress, and activation of HIF-1? and that HIF-1? contributes to CYP2E1-dependent ethanol-induced toxicity. Blocking HIF-1? activation and actions may have therapeutic implications for protection against ethanol/CYP2E1-induced oxidative stress, steatosis, and liver injury. PMID:23669278

Wang, Xiaodong; Wu, Defeng; Yang, Lili; Gan, Lixia; Cederbaum, Arthur I

2013-10-01

263

Investigation of xenobiotics metabolism, genotoxicity, and carcinogenicity using Cyp2e1(-/-) mice.  

PubMed

Cytochromes P450 (CYPs) comprise a number of enzyme subfamilies responsible for the oxidative metabolism of a wide range of therapeutic agents, environmental toxicants, mutagens, and carcinogens. In particular, cytochrome P450 2E1 (CYP2E1) is implicated in the oxidative bioactivation of a variety of small hydrophobic chemicals including a number of epoxide-forming drugs and environmentally important toxicants including urethane, acrylamide, acrylonitrile, benzene, vinyl chloride, styrene, 1-bromopropane, trichloroethylene, dichloroethylene, acetaminophen, and butadiene. Until recently, chemical modulators (inducers and inhibitors) were used in order to characterize the enzymatic basis of xenobiotic metabolism and the relationships between CYP-mediated bioactivation and chemical-induced toxicity/carcinogenicity. With the advent of genetically engineered knockout mice, the ability to evaluate the roles of specific CYPs in the metabolism of xenobiotics has become more attainable. The main focus of the current review is to present studies that characterized the enzymatic, metabolic, and molecular mechanisms of toxicity, genotoxicity, and carcinogenicity of various xenobiotics using Cyp2e1-/- mice. Data presented in this review demonstrated that the most comprehensive studies using Cyp2e1-/- mice, encompassing the entire paradigm of metabolism to toxicity, genotoxicity, and carcinogenicity were possible when a substrate was primarily metabolized via CYP2E1 (e.g. urethane and acrylamide). In contrast, when multiple CYP enzymes were prevalent in the oxidation of a particular substrate (e.g.: trichloroethylene, methacrylonitrile, crotononitrile), investigating the relationships between oxidative metabolism and biological activity became more complicated and required the use of chemical modulators. In conclusion, the current review showed that Cyp2e1-/- mice are a valuable animal model for the investigation of the metabolic and molecular basis of toxicity, genotoxicity, and carcinogenicity of xenobiotics. PMID:17979661

Ghanayem, Burhan I; Hoffler, Undi

2007-10-01

264

Inhibitory potency of 4-carbon alkanes and alkenes toward CYP2E1 activity.  

PubMed

CYP2E1 has been implicated in the bioactivation of many small molecules into reactive metabolites which form adducts with proteins and DNA, and thus a better understanding of the molecular determinants of its selectivity are critical for accurate toxicological predictions. In this study, we determined the potency of inhibition of human CYP2E1 for various 4-carbon alkanes, alkenes and alcohols. In addition, known CYP2E1 substrates and inhibitors including 4-methylpyrazole, aniline, and dimethylnitrosamine were included to determine their relative potencies. Of the 1,3-butadiene-derived metabolites studied, 3,4-epoxy-1-butene was the strongest inhibitor with an IC50 of 110 ?M compared to 1700 ?M and 6600 ?M for 1,2-butenediol and 1,2:3,4-diepoxybutane, respectively. Compared to known inhibitors, inhibitory potency of 3,4-epoxy-1-butene is between 4-methylpyrazole (IC50 = 1.8 ?M) and dimethylnitrosamine (IC50 = 230 ?M). All three butadiene metabolites inhibit CYP2E1 activity through a simple competitive mechanism. Among the 4-carbon compounds studied, the presence and location of polar groups seems to influence inhibitory potency. To further examine this notion, the investigation was extended to include structurally and chemically similar analogues, including propylene oxide and various butane alcohols. Those results demonstrated preferential recognition of CYP2E1 toward the type and location of polar and hydrophobic structural elements. Taken together, CYP2E1 metabolism may be modified in vivo by exposure to 4-carbon compounds, such as drugs, and nutritional constituents, a finding that highlights the complexity of exposure to mixtures. PMID:24561005

Hartman, Jessica H; Miller, Grover P; Boysen, Gunnar

2014-04-01

265

The dynamics of E1A in regulating networks and canonical pathways in quiescent cells  

PubMed Central

Background Adenoviruses force quiescent cells to re-enter the cell cycle to replicate their DNA, and for the most part, this is accomplished after they express the E1A protein immediately after infection. In this context, E1A is believed to inactivate cellular proteins (e.g., p130) that are known to be involved in the silencing of E2F-dependent genes that are required for cell cycle entry. However, the potential perturbation of these types of genes by E1A relative to their functions in regulatory networks and canonical pathways remains poorly understood. Findings We have used DNA microarrays analyzed with Bayesian ANOVA for microarray (BAM) to assess changes in gene expression after E1A alone was introduced into quiescent cells from a regulated promoter. Approximately 2,401 genes were significantly modulated by E1A, and of these, 385 and 1033 met the criteria for generating networks and functional and canonical pathway analysis respectively, as determined by using Ingenuity Pathway Analysis software. After focusing on the highest-ranking cellular processes and regulatory networks that were responsive to E1A in quiescent cells, we observed that many of the up-regulated genes were associated with DNA replication, the cell cycle and cellular compromise. We also identified a cadre of up regulated genes with no previous connection to E1A; including genes that encode components of global DNA repair systems and DNA damage checkpoints. Among the down-regulated genes, we found that many were involved in cell signalling, cell movement, and cellular proliferation. Remarkably, a subset of these was also associated with p53-independent apoptosis, and the putative suppression of this pathway may be necessary in the viral life cycle until sufficient progeny have been produced. Conclusions These studies have identified for the first time a large number of genes that are relevant to E1A's activities in promoting quiescent cells to re-enter the cell cycle in order to create an optimum environment for adenoviral replication.

2011-01-01

266

The E1/E2-preference of gastric H,K-ATPase mutants.  

PubMed

Gastric H,K-ATPase has, in the absence of ATP and added ions, a preference for the E(2) conformation. Mutations in the cation-binding pocket often result in a preference for the E(1)-conformation. This can be paralleled by the occurrence of K(+)-independent ATPase activity. These two phenomena could be separated by combined mutagenesis of several residues in and around the cation-binding pocket. Models of the three-dimensional structure of H,K-ATPase visualize the relationship between the E(1)/E(2) preference and the structure. PMID:12763793

De Pont, Jan Joep H H M; Swarts, Herman G P; Willems, Peter H G M; Koenderink, Jan B

2003-04-01

267

Anisotropy and Strength of Ceramic Bodies.  

National Technical Information Service (NTIS)

The experimental and theoretical efforts in the report can be divided into 5 groups: computation of the theoretical tensile, compressive and shear strength as depending on the orientation of the applied stress (bulk strength anisotropy) based on higher or...

W. R. Buessem H. A. McKinstry

1969-01-01

268

Tensile strength testing of Topopah Spring tuff.  

National Technical Information Service (NTIS)

Laboratory experiments were conducted to compare two techniques for determining the tensile strength of nonlithophysal, welded tuff of the Topopah Spring Member and determine which technique should be used for site characterization. Tensile strengths were...

L. W. Teufel M. J. McNamee

1991-01-01

269

Aluminum Rayleigh Taylor Strength Measurements and Calculations.  

National Technical Information Service (NTIS)

A traditional approach to the study of material strength has been revitalized at the Russian Federal Nuclear Center (VNIIEF). Rayleigh Taylor strength experiments have long been utilized to measure the material response of metals at high pressure and stra...

B. A. Remington K. T. Lorenz M. J. Lundquist R. M. Cavallo S. M. Pollaine V. A. Raevsky

2007-01-01

270

Naval Civil Engineer Corps Strength Study.  

National Technical Information Service (NTIS)

The report describes a simulation model and the accompanying computer program which computes the officer strength of the Civil Engineer Corps. The program requires as input, the officer strength as of a given date; the promotion, transfer, and retirement ...

H. A. Leupp

1968-01-01

271

Antibody directed to a synthetic peptide encoding the NH2-terminal 16 amino acids of the adenovirus type 2 E1B-53K tumor antigen recognizes the E1B-20K tumor antigen.  

PubMed

A peptide, H2N-Glu-Arg-Arg-Asn-Pro-Ser-Glu-Arg-Gly-Val-Pro-Ala-Gly-Phe-Ser-Gly-(Cys )COOH, containing the amino acid sequence at the NH2 terminus of the adenovirus type 2 (Ad2) E1B-coded large T antigen (E1B-53K) has been synthesized. Anti-peptide antibody was generated in rabbits and used to immunoprecipitate Ad T antigens from Ad2 early infected cell extracts. In addition to the expected E1B-53K T antigen, anti-peptide antibody precipitated the Ad2 E1B-20K T antigen that was previously shown to be related to E1B-53K (M. Green, K.H. Brackmann, M.A. Cartas, and T. Matsuo, J. Virol. 42, 30-41, 1982). Anti-peptide prepared against the COOH terminus of the E1B-53K T antigen or against the NH2 terminus of the E1B-19K T antigen did not precipitate the E1B-20K T antigen. These data suggest that the Ad2 E1B-20K T antigen initiates translation at nucleotide 2016 in reading frame 3, as does E1B-53K. The viral mRNA that encodes the E1B-20K T antigen has not been identified. PMID:6559483

Lucher, L A; Brackmann, K H; Symington, J S; Green, M

1984-01-15

272

Extensibility of high-strength concretes  

Microsoft Academic Search

This paper analyses the extensibility under flexural loads of concretes with 28-day compressive strength levels up to 80 MPa.\\u000a The major variables studied were loading rate, aggregate type, testing age and the environmental (moisture) conditions. It\\u000a is shown that extensibility increases with concrete strength but its variation is smaller than that of concrete strength.\\u000a It was verified that in high-strength

A. Giovambattista; D. Violini; R. Zerbino

1992-01-01

273

Absorption strength in absorbing chaotic cavities.  

PubMed

We derive an exact formula to calculate the absorption strength in absorbing chaotic systems such as microwave cavities or acoustic resonators. The formula allows us to estimate the absorption strength as a function of the averaged reflection coefficient and the real coupling parameter. We also define the weak and strong absorption regimes in terms of the coupling parameter and the absorption strength. PMID:18851122

Báez, G; Martínez-Mares, M; Méndez-Sánchez, R A

2008-09-01

274

Strength of nonuniformly oxidized PGX graphite  

Microsoft Academic Search

Flexural and tensile tests were performed on PGX graphite oxidized to produce a steep surface oxidation gradient. Companion tensile specimens were oxidized under different conditions to produce uniform oxidation throughout the specimen, and their tensile strength and Young's modulus were measured. The flexural strength, flexural elastic modulus, and tensile strength were reduced much less by surface oxidation than by uniform

R. J. Price; L. A. Beavan

1981-01-01

275

Grip Strength: Effect of Hand Dominance  

Microsoft Academic Search

Aim of the study: Reliable and valid evaluation of hand strength is important for determining the effectivity of treatment strategies and it is accepted that grip and pinch strength provide an objective index for the functional integrity of upper extremity. This study was designed to evaluate the grip and pinch strength differences between sides for the right and left handed

Nurgul Arinci Incel; Esma Ceceli; Pinar Bakici Durukan; H Rana Erdem

2002-01-01

276

GMTI tracking using signal strength information  

Microsoft Academic Search

Signal strength information is a standard output of a modern radar system. Provided the amplitude of the target returns exceeds the false alarm background, the consideration of signal strength may lead to improved target estimates, depending on the scenario. In this paper a Bayesian tracking algorithm is presented which incorporates the signal strength information. In contrast to previous approaches, the

Michael Mertens; Martin Ulmke

2010-01-01

277

Improving the toughness of ultrahigh strength steel  

SciTech Connect

The ideal structural steel combines high strength with high fracture toughness. This dissertation discusses the toughening mechanism of the Fe/Co/Ni/Cr/Mo/C steel, AerMet 100, which has the highest toughness/strength combination among all commercial ultrahigh strength steels. The possibility of improving the toughness of this steel was examined by considering several relevant factors.

Soto, Koji

2002-08-15

278

Two-phonon excitations in IR and NIR spectra of alunites  

NASA Astrophysics Data System (ADS)

Binary gerade-ungerade combinations of the fundamentals ?(OH/OD), ??(OH/OD), ??(OH/OD), and ?(SO 4), observed in IR and NIR spectra of alunite KAl 3(OH) 6(SO 4) 2, of its isotopomer alunite- d6 and of related compounds are discussed. With the ?(OH/OD) frequencies an anharmonicity analysis has been carried out. Calculation of overtone frequencies with consideration of anharmonicity and comparison of these values with the observed three quasi-overtones of ?(OH/OD) in the NIR spectra (actually combinations of the Raman- and IR-active fundamentals ?(OH/OD)) suggest that these quasi-overtones are strongly perturbed by resonances.

Breitinger, D. K.; Schukow, H.; Belz, H.-H.; Mohr, J.; Schwab, R. G.

1999-05-01

279

Strength evaluation of socket joints  

NASA Technical Reports Server (NTRS)

This report documents the development of a set of equations that can be used to provide a relatively simple solution for identifying the strength of socket joints and for most cases avoid the need of more lengthy analyses. The analytical approach was verified by comparison of the contact load distributions to results obtained from a finite element analysis. The contacting surfaces for the specific joint in this analysis are in the shape of frustrums of a cone and are representative of the tapered surfaces in the socket-type joints used to join segments of model support systems for wind tunnels. The results are in the form of equations that can be used to determine the contact loads and stresses in the joint from the given geometry and externally applied loads. Equations were determined to define the bending moments and stresses along the length of the joints based on strength and materials principles. The results have also been programmed for a personal computer and a copy of the program is included.

Rash, Larry C.

1994-01-01

280

Strength of Shocked Aluminum Oxynitride  

NASA Astrophysics Data System (ADS)

Aluminum oxynitride (AlON) is a polycrystalline and transparent ceramic. An accurate characterization of its shock response is critically important for its applications as transparent armor. Shock wave profiles measured in a series of plate impact experiments on AlON [Thornhill, et al., SCCM-2005, 143-146 (2006)] have been reanalyzed using finite element wave propagation simulations and considering an effective strength behavior that is pressure- and time-dependent. The results show a stiffer shock response than that calculated previously using the jump conditions. The material has a Hugoniot elastic limit of 10.37 GPa and sustains a maximum shear stress of 4.38 GPa for shock compressions up to a shock stress of 96 GPa. The mean stress response determined from the simulations displays no sign of phase transformation and corresponds to a linear shock speed-particle velocity relation with a slope of 0.857. These results have been successfully summarized into an AlON material model consisting of compression-dependent nonlinear elasticity, pressure-dependent equilibrium strength, and over-stress relaxation. The wave profiles simulated with the model show very good agreement with the experimental measurements.

Zhu, J.; Feng, R.; Dandekar, D. P.

2009-06-01

281

New intermediate strength fracture proppants  

SciTech Connect

A frac proppant's job is to hold a fracture open and allow fluids to flow readily toward the well bore. Sand most commonly is used as a frac proppant, but sand is not strong enough to hold a fracture open in many deep wells. In wells where the bottom hole treating pressure during the frac job exceeds the producing well-bore pressure by more than 6000 psi, sand may not have enough strength to hold the fracture open--or sand may be sufficiently crushed that it will not have enough permeability to allow a good production rate of oil or gas. If the closure pressure is as high as 10,000 psi, sand may be crushed so much that it is useless as a frac proppant. In wells where closure stresses range from 6000 to 12,000 psi, proppants are needed that are less expensive than sintered bauxite, but stronger than sand. This is the need that intermediate strength proppants are designed to fill. Their costs range from $.30 to $.65/lb. These costs combined with lower bulk densities make them considerably less expensive on a per cubic foot basis.

Sparlin, D.D.; Hagen, R.

1983-06-01

282

The Rationale for Prostaglandin E1 in Erectile Failure: A Survey of Worldwide Experience  

Microsoft Academic Search

PurposeProstaglandin E1 (PGE1, alprostadil) is used worldwide for self-injection therapy in erectile failure and was recently officially approved for this purpose in the United States and most European countries. Therefore a comprehensive overview on biochemistry, pharmacology and therapeutic results of PGE1 is provided.

Hartmut Porst

1996-01-01

283

Assessment of quantitative models for plasmid ColE1copy number control  

Microsoft Academic Search

Two quantitative models of plasmid ColE1 copy number control arecompared with respect to mathematical logic of derivation and application to experimental observations. Explanatory background material and clarifications are supplied for selected aspects of each model. Contrasting features are emphasized and experiments are suggested to distinguish between predictions of the models.

Sean Merlin; Barry Polisky

1995-01-01

284

Methylglyoxal induces oxidative stress and mitochondrial dysfunction in osteoblastic MC3T3-E1 cells.  

PubMed

Methylglyoxal is a reactive dicarbonyl compound produced by glycolytic processing and identified as a precursor of advanced glycation end products. The elevated methylglyoxal levels in patients with diabetes are believed to contribute to diabetic complications, including bone defects. The objective of this study was to evaluate the effect of methylglyoxal on the function of osteoblastic MC3T3-E1 cells. The data indicated that methylglyoxal decreased osteoblast differentiation and induced osteoblast cytotoxicity. Pretreatment of MC3T3-E1 cells with aminoguanidine (a carbonyl scavenger), Trolox (an antioxidant), and cyclosporin A (a blocker of the mitochondrial permeability transition pore) prevented methylglyoxal-induced cytotoxicity in MC3T3-E1 cells. However, BAPTA/AM (an intracellular Ca(2+) chelator) and dantrolene (an inhibitor of endoplasmic reticulum Ca(2+) release) did not reverse the cytotoxic effect of methylglyoxal. Methylglyoxal increased the formation of intracellular reactive oxygen species, mitochondrial superoxide, and cardiolipin peroxidation in osteoblastic MC3T3-E1 cells. Methylglyoxal also decreased the mitochondrial membrane potential and intracellular ATP and nitric oxide levels, suggesting that carbonyl stress-induced loss of mitochondrial integrity contributes to the cytotoxicity of methylglyoxal. Furthermore, the results demonstrated that methylglyoxal induced protein adduct formation, inactivation of glyoxalase I, and activation of glyoxalase II. Aminoguanidine reversed all aforementioned effects of methylglyoxal. Taken together, these data support the notion that high methylglyoxal concentrations have detrimental effects on osteoblasts through a mechanism involving oxidative stress and mitochondrial dysfunction. PMID:24164256

Suh, K S; Choi, E M; Rhee, S Y; Kim, Y S

2014-02-01

285

A preliminary map of epitopes on envelope glycoprotein E1 of HCV strain Brescia.  

PubMed

Monoclonal antibodies (MAbs) directed against envelope glycoprotein E1 (gp51-54) of hog cholera virus (HCV) strain Brescia have been shown to recognize four different antigenic domains A, B, C and D. Epitopes of within domain A have mainly been found conserved among HCV strains, whereas epitopes within domains B, C and D are not conserved. We used transiently expressed hybrid E1 genes of HCV strains Brescia and "C" to map the non-conserved epitopes on E1. Epitopes in domains B and C are located within the ultimate N-terminal 104 amino acids. The non-conserved subdomain A3 is most probably located between domains B/C and a hydrophobic region, which is highly conserved between HCV strains Brescia and "C". The conserved subdomains A1 and A2 are probably located in the vicinity and C-terminally of this conserved, hydrophobic region, which is near the centre of the E1 amino acid sequence. PMID:1282755

van Rijn, P A; van Gennip, R G; de Meijer, E J; Moormann, R J

1992-11-01

286

Enhanced E1 transitions and {alpha}-clustering in {sup 212}Po  

SciTech Connect

An {alpha}+{sup 208}Pb(0{sup +},3{sup -}) cluster model explains the recently observed enhanced E1 transitions from the new negative-parity levels to the yrast states in {sup 212}Po. Heavy and light nuclei present good examples of surface clustering and well-localized clustering.

Suzuki, Y. [Department of Physics, Niigata University, Niigata 950-2181 (Japan); Ohkubo, S. [Department of Applied Science and Environment, Kochi Women's University, Kochi 780-8515 (Japan)

2011-05-06

287

Evaluation of E1Mutant Adenoviruses as Conditionally Replicating Agents for Cancer Therapy  

Microsoft Academic Search

The oncolytic effect of adenoviruses may provide an efficient means to destroy tumor tissue if viruses could be developed with sufficient selectivity and efficacy. In this report we have characterized several adenoviruses, each with different mutations in the E1 region, for selective cytopathic effect in tumor cells in vitro and for their ability to inhibit tumor growth in vivo. Of

John A. Howe; G. William Demers; Duane E. Johnson; Sarah E. A. Neugebauer; Stuart T. Perry; Mei Ting Vaillancourt; Barbara Faha

2000-01-01

288

Effects of Herbal Products and their Constituents on Human Cytochrome P4502E1 Activity  

PubMed Central

Ethanolic extracts from fresh Echinacea purpurea and Spilanthes acmella and dried Hydrastis canadensis were examined with regard to their ability to inhibit cytochrome P4502E1 mediated oxidation of p-nitrophenol in vitro. In addition, individual constituents of these extracts, including alkylamides from E. purpurea and S. acmella, caffeic acid derivatives from E. purpurea, and several of the major alkaloids from H. canadensis, were tested for inhibition using the same assay. H. canadensis (goldenseal) was a strong inhibitor of the P4502E1, and the inhibition appeared to be related to the presence of the alkaloids berberine, hydrastine and canadine in the extract. These compounds inhibited 2E1 with KI values ranging from 2.8 µM for hydrastine to 18 µM for berberine. The alkylamides present in E. purpurea and S. acmella also showed significant inhibition at concentrations as low as 25 µM, whereas the caffeic acid derivatives had no effect. Commercial green tea preparations, along with four of the individual tea catechins, were also examined and were found to have no effect on the activity of P4502E1.

Raner, Gregory M.; Cornelious, Sean; Moulick, Kamalika; Wang, Yingqing; Mortenson, Ashley; Cech, Nadja B.

2010-01-01

289

Precise orbit determination of Smart-1 and Chang'E-1  

NASA Astrophysics Data System (ADS)

The Smart-1 was tracked by Chinese VLBI network and USB stations from 28 May, 2006 to 2 June, 2006 as a test for Chinese deep space network tracking ability, precise orbit determination was processed combining VLBI delay, delay rate and Doppler data. The reaction wheel unloadings were considered in long arc orbit determination, it showed good consistency with reconstructed orbit provided by ESA, the strategy used in smart-1 was used in Chang'E-1 precise orbit determination. Chang'E-1 was launched at 24 Oct, 2007, one of the main scientific objections is to map the lunar surface and get 3-D lunar topography model by satellite laser altimetry. The precise orbit determination of Chang'E-1 was realized by combining VLBI and USB data using GEODYNII/SOVLE software of GSFC/NASA/USA (Rowland,1997; Ullman,1994),, the frequently reaction wheel unloadings are considered in order to get high accuracy and continuous orbit, which can attribute to the laser altimetry data process and possible lunar gravity field recovery. Keywords: smart-1, Chang'E-1, precise orbit determination, reaction wheel unloading

Jianguo, Yan; Ping, Jing-Song; Li, Fei

290

The effect of prostaglandin E1 analog misoprostol on chronic cyclosporin nephrotoxicity.  

PubMed

Cyclosporin A has markedly improved graft survival in transplant patients but its side effects, such as renal toxicity and hypertension, pose management problems in transplant recipients. This toxicity has been attributed to prostaglandin inhibition. Concurrent administration of misoprostol (a prostaglandin E1 analog) prevents chronic cyclosporin A-induced nephrotoxicity but not hypertension in rats. PMID:8301454

John, E G; Fornell, L C; Radhakrishnan, J; Anutrakulchai, S; Jonasson, O

1993-11-01

291

NOVEL ASSAY TO ASSESS CYP-2E1-LIKE ACTIVITY IN THE JAPANESE MEDAKA (ORYZIAS LATIPES).  

EPA Science Inventory

Liver microsomes and S-9 fraction of Japanese medaka (Oryzias latipes) metabolized the CYP2E1 specific substrate, p-nitrophenol (PNP), to a single hydroxylated product, 4-nitrocatechol. The use of liver S-9 fraction proved to be a viable alternative to liver microsomes and allowe...

292

Atomic Theory of Parity-Odd (E1-M1) Photon Absorption Event  

NASA Astrophysics Data System (ADS)

Light scattering proceeding through electric and magnetic dipole absorption events (E1-M1) exhibits natural circular dichroism, widely used in the characterization of chiral media, and the magneto-chiral effect, which is under consideration as a mechanism for the homo-chirality of life. Additional manifestations of E1-M1 scattering are resonance enhanced Bragg diffraction and non-reciprocal linear dichroism. In spite of its established importance for a raft of significant phenomena, there has not been a complete treatment of E1-M1 light scattering by electrons. Starting from the interaction that includes both electron spin and angular momentum variables, we construct scattering that proceeds via a spin-orbit split intermediate state for the photo-ejected electron. Employing new relations for re-coupling angular momentum we give a theoretical basis for the derivation of sum-rules for integrated dichroic signals. In order to assist in the interpretation of the algebraic terms present for E1-M1 we construct a family of equivalent operators that include monopoles for chirality and magnetic charge. Worked examples of corresponding expectation values are given for two sample wave functions to demonstrate the flavour and support the use of specific equivalent tensor operators.

Stephen William Lovesey,; Ewald Balcar,

2010-07-01

293

Tumor Suppression and Sensitization to Taxol Induced Apoptosis of E1A in Breast Cancer Cells.  

National Technical Information Service (NTIS)

The purpose of this project is to study the molecular mechanisms underlying ElA's proapoptotic effect and anti-tumor activity and to dissect the functional domains of ElA that are critical for its antitumor activity. Because a phase I E1A gene therapy pro...

Y. Liao

2002-01-01

294

The roles of ER stress and P450 2E1 in CCl(4)-induced steatosis.  

PubMed

The role of ER stress on hepatic steatosis was investigated in a rat model. We injected CCl(4) into rats and found that CCl(4) could induce hepatic lipid accumulation, confirmed by Oil Red O staining and by measurement of triglyceride and cholesterol. The expression of ApoB, an apolipoprotein, was decreased in plasma and increased in the liver of CCl(4)-treated animals. The ER stress response was also significantly increased by CCl(4). P450 2E1 expression and activity were increased through interactions of P450 2E1 with NADPH-dependent P450 reductase (NPR) under CCl(4)-treated conditions. In HepG2 cells, intracellular lipid accumulation and its signaling were comparable to in vivo results. In order to elucidate the effect of the ER stress response itself, tunicamycin, an N-acetyl-glycosylation inhibitor, was injected into rats, followed by Oil Red O staining, lipid/triglyceride/cholesterol accumulation analysis, and examination of ApoB expression. Additionally, the ER stress response and upregulation of P450 2E1 were also confirmed in the tunicamycin-treated rats. All of the responses were similar to those seen with CCl(4). The P450 2E1 inhibitor diallyl sulphide (DAS), N-acetylcysteine (NAC), and reduced glutathione (GSH) antioxidants also regulated processes, including ApoB expression and lipid accumulation in CCl(4)-treated animals. In the presence of tunicamycin, DAS or NAC/GSH regulated all of the pathological phenomena with the exception of the ER stress response. In summary, CCl(4) induces liver steatosis, a process involving ER stress-induced P450 2E1 activation and ROS production. PMID:21722752

Lee, Geum-Hwa; Bhandary, Bidur; Lee, Eun-Mi; Park, Jin-Kyu; Jeong, Kyu-Shik; Kim, In-Ki; Kim, Hyung-Ryong; Chae, Han-Jung

2011-10-01

295

A Golgi retention signal in a membrane-spanning domain of coronavirus E1 protein  

PubMed Central

The E1 glycoprotein from an avian coronavirus is a model protein for studying retention in the Golgi complex. In animal cells expressing the protein from cDNA, the E1 protein is targeted to cis Golgi cisternae (Machamer, C. E., S. A. Mentone, J. K. Rose, and M. G. Farquhar. 1990. Proc. Natl. Acad. Sci. USA. 87:6944-6948). We show that the first of the three membrane-spanning domains of the E1 protein can retain two different plasma membrane proteins in the Golgi region of transfected cells. Both the vesicular stomatitis virus G protein and the alpha- subunit of human chorionic gonadotropin (anchored to the membrane by fusion with the G protein membrane-spanning domain and cytoplasmic tail) were retained in the Golgi region of transfected cells when their single membrane-spanning domains were replaced with the first membrane- spanning domain from E1. Single amino acid substitutions in this sequence released retention of the chimeric G protein, as well as a mutant E1 protein which lacks the second and third membrane-spanning domains. The important feature of the retention sequence appears to be the uncharged polar residues which line one face of a predicted alpha helix. This is the first retention signal to be defined for a resident Golgi protein. The fact that it is present in a membrane-spanning domain suggests a novel mechanism of retention in which the membrane composition of the Golgi complex plays an instrumental role in retaining its resident proteins.

1991-01-01

296

Strain rate, temperature, and humidity on strength and moduli of a graphite/epoxy composite  

NASA Technical Reports Server (NTRS)

Results of an experimental study of the influence of strain rate, temperature and humidity on the mechanical behavior of a graphite/epoxy fiber composite are presented. Three principal strengths (longitudinal, transverse and shear) and four basic moduli (E1, E2, G12 and U12) of a unidirectional graphite/epoxy composite were followed as a function of strain rate, temperature and humidity. Each test was performed at a constant tensile strain rate in an environmental chamber providing simultaneous temperature and humidity control. Prior to testing, specimens were given a moisture preconditioning treatment at 60 C. Values for the matrix dominated moduli and strength were significantly influenced by both environmental and rate parameters, whereas the fiber dominated moduli were not. However, the longitudinal strength was significantly influenced by temperature and moisture content. A qualitative explanation for these observations is presented.

Lifshitz, J. M.

1981-01-01

297

Correlation of Yield Strength and Tensile Strength with Hardness for Steels  

NASA Astrophysics Data System (ADS)

Hardness values as well as yield and tensile strength values were compiled for over 150 nonaustenitic, hypoeutectoid steels having a wide range of compositions and a variety of microstructures. The microstructures include ferrite, pearlite, martensite, bainite, and complex multiphase structures. The yield strength of the steels ranged from approximately 300 MPa to over 1700 MPa. Tensile strength varied over the range of 450-2350 MPa. Regression analysis was used to determine the correlation of the yield strength and the tensile strength to the diamond pyramid hardness values for these steels. Both the yield strength and tensile strength of the steels exhibited a linear correlation with the hardness over the entire range of strength values. Empirical relationships are provided that enable the estimation of strength from a bulk hardness measurement. A weak effect of strain-hardening potential on the hardness-yield strength relationship was also observed.

Pavlina, E. J.; van Tyne, C. J.

2008-12-01

298

CYP2E1 immunoglobulin G4 subclass antibodies after desflurane anesthesia  

PubMed Central

AIM: To investigate CYP2E1 IgG4 autoantibody levels and liver biochemical markers in adult patients after anesthesia with desflurane. METHODS: Forty patients who were > 18 years old and undergoing elective surgery under general anesthesia with desflurane were studied. Alpha-glutathione-S-transferase (?GST) and IgG4 antibodies against CYP2E1 were measured preoperatively and 96 h postoperatively, as well as complete blood count, prothrombin time (PT), activated partial thromboplastin time (aPTT), international normalized ratio (INR), aspartate aminotransferase (SGOT), alanine aminotransferase (SGPT), g-glutamyl-transpeptidase (gGT), alkaline phosphatase, total serum proteins, albumin and bilirubin. A separate group of 8 patients who received regional anesthesia was also studied for calibration of the methodology used for CYP2E1 IgG4 and ?GST measurements. Student’s t-test and the Mann-Whitney U test were used for comparison of the continuous variables, and Fisher’s exact test was used for the categorical variables. All tests were two-tailed, with statistical significance set as P < 0.05. RESULTS: None of the patients developed postoperative liver dysfunction, and all patients were successfully discharged from the hospital. No statistically significant difference was observed regarding liver function tests (SGOT, SGPT, ?GT, bilirubin, INR), ?GST and CYP2E1 IgG4, before and after exposure to desflurane. After dividing patients into two subgroups based on whether or not they had received general anesthesia in the past, no significant difference in the levels of CYP2E1 IgG4 was observed at baseline or 96 h after desflurane administration (P = 0.099 and P = 0.051, respectively). Alpha-GST baseline levels and levels after the intervention also did not differ significantly between these two subgroups (P > 0.1). The mean ?GST differences were statistically elevated in men by 2.15 ng/mL compared to women when adjusted for BMI, duration of anesthesia, number of times anesthesia was administered previously and length of hospital stay. No significant difference was observed between patients who received desflurane and those who received regional anesthesia at any time point. CONCLUSION: There was no difference in CYP2E1 IgG4 or ?GST levels after desflurane exposure; further research is required to investigate their role in desflurane-induced liver injury.

Batistaki, Chrysanthi; Michalopoulos, George; Matsota, Paraskevi; Nomikos, Tzortzis; Kalimeris, Konstantinos; Riga, Maria; Nakou, Maria; Kostopanagiotou, Georgia

2014-01-01

299

Axl-Gas6 Interaction Counteracts E1A-Mediated Cell Growth Suppression and Proapoptotic Activity  

PubMed Central

The adenovirus type 5 early region 1A gene (E1A) has previously been known as an immortalization oncogene because E1A is required for transforming oncogenes, such as ras and E1B, to transform cells in primary cultures. However, E1A has also been shown to downregulate the overexpression of the Her-2/neu oncogene, resulting in suppression of transformation and tumorigenesis induced by that oncogene. In addition, E1A is able to promote apoptosis induced by anticancer drugs, irradiation, and serum deprivation. Many tyrosine kinases, such as the epidermal growth factor receptor, Her-2/Neu, Src, and Axl, are known to play a role in oncogenic signals in transformed cells. To study the mechanism underlying the E1A-mediated tumor-suppressing function, we exploited a modified tyrosine kinase profile assay (D. Robinson, F. Lee, T. Pretlow, and H.-J. Kung, Proc. Natl. Acad. Sci. USA 93:5958–5962, 1996) to identify potential tyrosine kinases regulated by E1A. Reverse transcription (RT)-PCR products were synthesized with two degenerate primers derived from the conserved motifs of various tyrosine kinases. A tyrosine kinase downregulated by E1A was identified by analyzing the AluI-digested RT-PCR products. We isolated the DNA fragment of interest and found that E1A negatively regulated the expression of the transforming receptor tyrosine kinase Axl at the transcriptional level. To study whether downregulation of the Axl receptor is involved in E1A-mediated growth suppression, we transfected axl cDNA into E1A-expressing cells (ip1-E1A) to establish cells that overexpressed Axl. The Axl ligand Gas6 triggered a greater mitogenic effect in these ip1-E1A-Axl cells than in ip1-E1A control cells and protected the Axl-expressing cells from serum deprivation-induced apoptosis. These results indicate that downregulation of the Axl receptor by E1A is involved in E1A-mediated growth suppression and E1A-induced apoptosis and thereby contributes to E1A’s antitumor activities.

Lee, Wei-Ping; Liao, Yong; Robinson, Dan; Kung, Hsing-Jien; Liu, Edison T.; Hung, Mien-Chie

1999-01-01

300

Reaction mechanism of the heterotetrameric (alpha2beta2) E1 component of 2-oxo acid dehydrogenase multienzyme complexes.  

PubMed

Pyruvate decarboxylase (E1) catalyzes the first two reactions of the four involved in oxidative decarboxylation of pyruvate by the pyruvate dehydrogenase (PDH) multienzyme complex. It requires thiamin diphosphate to bring about the decarboxylation of pyruvate, which is followed by the reductive acetylation of a lipoyl group covalently bound to the N(6) amino group of a lysine residue in the second catalytic component, a dihydrolipoyl acetyltransferase (E2). Replacement of two histidine residues in the E1alpha and E1beta chains of the heterotetrameric E1 (alpha(2)beta(2)) component of the PDH complex of Bacillus stearothermophilus, considered possible proton donors at the active site, was carried out. Subsequent characterization of the mutants permitted different roles to be assigned to these two particular residues in the reaction catalyzed by E1: E1alpha His271 to stabilize the dianion formed during decarboxylation of the 2-oxo acid and E1beta His128 to provide the proton required to protonate the incoming dithiolane ring in the subsequent reductive acetylation of the lipoyl goup. On the basis of these and other results from a separate investigation into the roles of individual residues in a loop region in the E1alpha chain close to the active site of E1 [Fries, M., Chauhan, H. J., Domingo, G. J., Jung, H., and Perham, R. N. (2002) Eur. J. Biochem. 270, 861-870] together with work from other laboratories, a detailed mechanism for the E1 reaction can be formulated. PMID:12795594

Fries, Markus; Jung, Hyo-Il; Perham, Richard N

2003-06-17

301

Polymorphisms in the CYP2E1 and GSTM1 Genes as Possible Protection Factors for Leprosy Patients  

PubMed Central

Background The CYP2E1 and GSTM1 genes encode metabolic enzymes that have key functions in drug modification and elimination. Methodology/Principal Findings We investigated the possible effects of CYP2E1 and GSTM1 polymorphisms in 71 leprosy patients and in 110 individuals from the general population. The GSTM1*0 null allele and INDEL CYP2E1*1D mutant genotypes were analyzed by conventional PCR, while CYP2E1 SNPs (1053C>T, 1293G>C and 7632T>A) were determined by RT-PCR. In leprosy patients, the GSTM1*0 and CYP2E1*5 alleles and the combined alleles GSTM1*0/CYP2E1*6 and GSTM1*0/CYP2E1*5 were significantly related to a baciloscopic index (BI) (BI<3), while the CYP2E1*6 allele was related to a better clinical evolution in the leprosy spectrum. Conclusions/Significance Therefore, GSTM1*0, CYP2E1*5 and CYP2E1*6 may be possible protection factors for leprosy patients.

Pinto, Pablo; Salgado, Claudio Guedes; Santos, Ney; Alencar, Dayse O.; Santos, Sidney; Hutz, Mara H.; Ribeiro-dos-Santos, Andrea

2012-01-01

302

Chimeric Derivatives of Hepatitis B Virus Core Particles Carrying Major Epitopes of the Rubella Virus E1 Glycoprotein  

PubMed Central

Three variants of the major rubella virus (RV) E1 protein virus-neutralizing epitope from position 214 to 285 were exposed on the hepatitis B virus (HBV) C-terminally truncated core (HBc?) in a virus-like particle (VLP) vector and were produced in Escherichia coli. All three chimeras demonstrated VLPs in bacterial cell lysates, but only HBc?-E1(245-285) demonstrated the correct VLP structure after purification. The other chimeras, HBc?-E1(214-285) and HBc?-E1(214-240), appeared after purification as non-VLP aggregates of 100 to 900 nm in diameter according to dynamic light scattering data. All three variants possessed the intrinsic antigenic activity of RV E1, since they were recognized by natural human anti-RV E1 antibodies and induced an anti-RV E1 response in mice. HBc?-E1(214-240) and HBc?-E1(245-285) can be regarded as prototypes for a putative RV vaccine because they were able to induce antibodies recognizing natural RV E1 protein in RV diagnostic kits.

Skrastina, Dace; Petrovskis, Ivars; Petraityte, Rasa; Sominskaya, Irina; Ose, Velta; Lieknina, Ilva; Bogans, Janis; Sasnauskas, Kestutis

2013-01-01

303

The adenovirus E1A transforming protein activates the proliferating cell nuclear antigen promoter via an activating transcription factor site.  

PubMed Central

The transforming region of adenovirus (E1) stimulates expression of a reporter construct linked to the promoter for the human proliferating cell nuclear antigen (PCNA) gene in a cotransfection assay (G. F. Morris and M. B. Mathews, J. Biol. Chem. 264:13856-13864, 1989). The major products of the E1 region were assessed individually for their contribution to transactivation of the PCNA promoter. The E1A 13S and 12S products and the E1B 19-kDa product elevated expression from the PCNA promoter, whereas the E1B 55-kDa product did not. Induction of the PCNA promoter by E1A differed from transcriptional activation of the adenovirus E3 promoter in that the PCNA promoter is activated by the E1A 12S product whereas the E3 promoter is repressed; furthermore, the PCNA promoter is activated upon E1A overexpression, whereas the E3 promoter responds less well to high amounts of E1A. A site for the activating transcription factor ATF located approximately 50 nucleotides upstream from the transcription initiation site in the PCNA promoter mediates a positive response to the E1A 12S and 13S products. Images

Morris, G F; Mathews, M B

1991-01-01

304

Purification, crystallization and preliminary X-ray diffraction analysis of human enolase-phosphatase E1  

PubMed Central

Enolase-phosphatase E1 (MASA) is a bifunctional enzyme in the ubiquitous methionine-salvage pathway and catalyzes the continuous reaction of 2,3-­diketo-5-methylthio-1-phosphopentane to yield the acireductone metabolite. Recombinant human E1 enzyme has been crystallized using the hanging-drop vapour-diffusion method and diffraction-quality crystals were grown at 291?K using PEG 4000 as precipitant. Diffraction data were collected to 1.7?Å resolution from SeMet-derivative crystals at 100?K using synchrotron radiation. The crystals belong to space group P212121, with unit-cell parameters a = 54.02, b = 57.55, c = 87.32?Å. The structure was subsequently solved by the multi-wavelength anomalous diffraction (MAD) phasing method.

Wang, Hui; Pang, Hai; Ding, Yi; Li, Yi; Wu, Xiao'ai; Rao, Zihe

2005-01-01

305

Throughput Calibration of the 52x0.2E1 Aperture  

NASA Astrophysics Data System (ADS)

The Next Generation Spectral Library {NGSL} is a library of low-dispersion STIS spectra extending from 0.2-1.0 microns. So far, 378 stars with a wide range in metallicity have been observed. Despite their high S/N>100, many NGSL spectra have 5-10% systematic errors in their spectral energy distributions, which can be traced to throughput variations in the 52x0.2E1 aperture caused by vignetting of a wavelength-dependent asymmetric PSF. We propose to obtain STIS spectra of the HST standard star, BD+75D325, at several positions in the 52x0.2E1 aperture, which will enable us to calibrate the NGSL spectra properly.;

Heap, Sara

2008-07-01

306

Investigation and remediation of false topographic perception phenomena observed on Chang'E-1 lunar imagery  

NASA Astrophysics Data System (ADS)

False topographic perception phenomenon (FTPP) is a relief inversion phenomenon in remote sensing images and causes false perception problems. Such images of the Moon suffer from serious FTPP problems. Correctly observing and understanding the terrain features on the Moon from lunar surface images is important for lunar exploration missions and various lunar scientific investigations. This paper presents a systematic investigation of the FTPP problem associated with lunar craters, by using the Chang'E-1 lunar imagery covering the major areas of the lunar surface. Results reveal that the FTPP problem is positively correlated with crater latitudes in the north hemisphere of the Moon. For craters within a similar latitude range, the FTPP level is positively correlated with the depth-diameter ratio of the crater. A wavelet-transform based approach is proposed for FTPP remediation on Chang'E-1 imagery. Experimental analysis using three different types of craters revealed that the approach is able to effectively correct the FTPP problem.

Wu, Bo; Li, Haifeng; Gao, Yang

2013-01-01

307

Interpretation of the accidental predissociation of the E1? state of CO  

NASA Astrophysics Data System (ADS)

A special case of predissociation, known as indirect or accidental predissociation observed in the Rydberg E1? bound state of CO is discussed. We resort to ab initio potentials in order to determine the plausible mechanism for this predissociation. Values of the predissociation width for the valence k3? state of CO, as obtained from Fermi's golden rule, are also reported. The predissociation width obtained for the mixed E1? (v = 1, J = 7) state is 0.033 cm-1 compared to the experimental value of 0.034 cm-1. The mixed E - E' state with J = 28, v = 0 is found to be in near resonance condition with the k3? (v = 4, J = 28) state, thus providing the means to indirect predissociation.

Majumder, M.; Sathyamurthy, N.; Vázquez, G. J.; Lefebvre-Brion, H.

2014-04-01

308

Interpretation of the accidental predissociation of the E(1) ? state of CO.  

PubMed

A special case of predissociation, known as indirect or accidental predissociation observed in the Rydberg E(1)? bound state of CO is discussed. We resort to ab initio potentials in order to determine the plausible mechanism for this predissociation. Values of the predissociation width for the valence k(3)? state of CO, as obtained from Fermi's golden rule, are also reported. The predissociation width obtained for the mixed E(1)? (v = 1, J = 7) state is 0.033 cm(-1) compared to the experimental value of 0.034 cm(-1). The mixed E - E(') state with J = 28, v = 0 is found to be in near resonance condition with the k(3)? (v = 4, J = 28) state, thus providing the means to indirect predissociation. PMID:24784266

Majumder, M; Sathyamurthy, N; Vázquez, G J; Lefebvre-Brion, H

2014-04-28

309

Ultrasound associated uptake of chitosan nanoparticles in MC3T3-E1 cells  

NASA Astrophysics Data System (ADS)

Chitosan is a natural linear polysaccharide that has been well known for its applications in drug delivery system due to its unique physicochemical and biological properties. However, challenges still remain for it to become a fully realized therapeutic agent. In this study, we investigated the uptake of chitosan nanoparticles (CNP) under the ultrasound stimulation, using a model cell culture system (MC3T3-E1 mouse pre-osteoblasts). The CNP were fabricated by an ionic gelation method and were lyophilized prior to characterization and delivery to cells. Particle size and zeta potential were measured using Dynamic Light Scattering (DLS); the efficiency of chitosan complexation was measured using the ninhydrin assay. Cytotoxicity was examined by neutral red assay within 48 hours after delivery. The effect of ultrasound (US) on the efficiency of nanoparticle delivery to the MC3T3-E1 cells was examined at 1MHz and at either 1 or 2 W/cm2. Fluorescein isothiocyanate (FITC)-conjugated-CNP were used to visualize the internalized particles within the cytosol. The uptake of FITC-CNP exhibits a dose and time dependent effect, a strong FITC fluorescence was detected at the concentration of 500microg/mL under fluorescence microscope. Ultrasound assisted uptake of FITC-CNP performed a significant positive effect at 2W/cm2 with 60s of ultrasound exposure time. CNP displayed a slightly decrease in cell viability from 25microg/mL to 100microg/mL, while higher concentration of CNP facilitates the proliferation of MC3T3-E1 cells. Less than 10% of reduction in cell viability was observed for US at 1W/cm2 and 2W/cm2 with 30s and 60s of exposure time, which suggest a mild effect of US to MC3T3-E1 cell line.

Wu, Junyi

310

Joint Tracking of Chang'E-1 with VLBI and USB  

Microsoft Academic Search

Chinese lunar exploration mission Chang'E-I made use of a Chinese Unified S-Band (USB) system and a network of four Very Long Baseline Interferometry (VLBI) antennas to meet the orbit determination\\/predication requirements of spacecraft tracking and scientific data analysis, which for the first time handled telemetry and control for a spacecraft at a distance of about 380,000 km. Chang'E-1 provided a

Xiaogong Hu

2008-01-01

311

Calculation of Radiative Corrections to E1 matrix elements in the Neutral Alkalis  

SciTech Connect

Radiative corrections to E1 matrix elements for ns-np transitions in the alkali metal atoms lithium through francium are evaluated. They are found to be small for the lighter alkalis but significantly larger for the heavier alkalis, and in the case of cesium much larger than the experimental accuracy. The relation of the matrix element calculation to a recent decay rate calculation for hydrogenic ions is discussed, and application of the method to parity nonconservation in cesium is described.

Sapirstein, J; Cheng, K T

2004-09-28

312

Simvastatin Promotes Osteoblast Differentiation and Mineralization in MC3T3-E1 Cells  

Microsoft Academic Search

The cholesterol-lowering drug, simvastatin, is a pro-drug of a potent 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor and inhibits cholesterol synthesis in humans and animals. In addition, the bone effects of statins including simvastatin are being studied. We assessed the effects of simvastatin on osteoblastic differentiation in nontransformed osteoblastic cells (MC3T3-E1) and rat bone marrow cells. Simvastatin enhanced alkaline phosphatase (ALP) activity

Toyonobu Maeda; Ayako Matsunuma; Tetsuya Kawane; Noboru Horiuchi

2001-01-01

313

Calculation of lunar Bouguer gravity anomaly using Chang'E-1 topography data: Interpretation for mascons  

Microsoft Academic Search

Bouguer gravity anomaly (BGA) reveals density structures of planets. Using the new lunar topography data measured by Chang'E-1 Laser Altimeter, we have calculated the Bouguer gravity anomaly (BGA) of the Moon based on gravity field model LP165P. Two different terrain correction (i.e., Bouguer correction) methods are compared. One is using spheric harmonic coefficients of topography model (CLTM-s01) to directly derive

Q. Liang; C. Chen; J. Du; B. Chen

2009-01-01

314

Purification of supercoiled DNA of plasmid Col E1 by RPC-5 chromatography  

SciTech Connect

Col E1 DNA can be purified to a high degree by RPC-5 chromatography of a partially purified cell lysate with a very shallow linear NaC1 gradient at pH 7.8. Electron micrographs demonstrated that the purest fractions were composed of 93% supercoiled (form I) DNA and 7% open circular (form II) DNA. The actual chromatography can be accomplished in 13 to 14 h and is designed for the production of several milligrams of plasmid DNA.

Best, A.N.; Allison, D.P.; Novelli, G.D.

1981-07-01

315

The characteristics of neutrino-nuclear reactions at E ? = 1-3 GeV  

NASA Astrophysics Data System (ADS)

The characteristics of the charged-current neutrino—nuclear interactions are investigated for the first time at E ? = 1-3 GeV using the data obtained with SKAT propane-freon bubble chamber irradiated in the neutrino beam at the Serpukhov accelerator. The E ? dependence of the mean multiplicities of different types of secondary particles and their multiplicity, momentum, and angular distributions are measured.

Agababyan, N. M.; Ammosov, V. V.; Atayan, M.; Grigoryan, N.; Gulkanyan, H.; Ivanilov, A. A.; Karamyan, Zh.; Korotkov, V. A.

2007-11-01

316

Biochemical and genetic studies of four patients with pyruvate dehydrogenase E1? deficiency  

Microsoft Academic Search

We report studies of four patients with pyruvate dehydrogenase complex (PDH) deficiency caused by mutations in the E1? subunit.\\u000a Two unrelated male patients presented with Leigh syndrome and a R263G missense mutation in exon 8. This mutation has previously\\u000a been described in males with the same phenotype. The two other patients had different novel mutations: (1) an 8-bp deletion\\u000a at

Cécile Marsac; Chantal Benelli; Isabelle Desguerre; Monique Diry; Françoise Fouque; Linda De Meirleir; Gérard Ponsot; Sara Seneca; Florence Poggi; Jean-Marie Saudubray; Marie-Thérèse Zabot; Daniel Fontan; Willy Lissens

1997-01-01

317

l Carnitine protects against apoptosis of murine MC3T3-E1 osteoblastic cells  

Microsoft Academic Search

Summary.  \\u000a l-Carnitine (LC), an amino acid with a major role in cellular energy metabolism, has positive effects on bone metabolism. However,\\u000a the effect of LC on apoptosis of osteoblast in vitro has not been reported. The aim of this study was to investigate the action\\u000a of LC on apoptosis of mouse osteoblastic cell line MC3T3-E1. Cell apoptosis was measured by

H. Xie; S.-Y. Tang; H. Li; X.-H. Luo; L.-Q. Yuan; D. Wang; E.-Y. Liao

2008-01-01

318

Risk assessment: toxicity from chemical exposure resulting from enhanced expression of CYP2E1  

Microsoft Academic Search

Humans are continuously exposed to a wide variety of xenobiotics either voluntarily or from environmental exposure. Many xenobiotics including pesticides, nitrosamines, polycyclic aromatic hydrocarbons and halogenated hydrocarbons, require bioactivation by P450 enzymes to elicit toxicity. CYP2E1 is considered to be toxicologically important in humans because of its capacity to produce intermediates that promote cytotoxicity and\\/or carcinogenic- ity from a number

Judy L. Raucy

1995-01-01

319

Migraine: possible role of platelet insensitivity to prostaglandin E1 (PGE1).  

PubMed

Platelet aggregation inhibition, induced by prostaglandin E1 (PGE1), was evaluated in 38 patients affected by migraine. Our data indicate a complete insensitivity to PGE1 in these subjects. The insensitivity to PGE1 leads to decreased cyclic-AMP (cAMP) levels, determining an imbalance in the inhibitory mechanism. From this observation we can suppose that the decreased affinity of PGE1-receptors, causing decreased cAMP levels, may be involved in pathogenesis of migraine. PMID:8150318

Cerneca, F; de Luyk, S; Radillo, O; Simeone, R; Mangiarotti, M

1993-01-01

320

Chang’E-1 gamma ray spectrometer and preliminary radioactive results on the lunar surface  

Microsoft Academic Search

The Chang’E-1(CE-1) spacecraft took a gamma-ray spectrometer (hereafter, CGRS) to detect the element distributions on the lunar surface in a circular, 200km altitude, polar orbit with approximately 2h periodicity. CGRS consists of two large CsI(Tl) crystals as the main and anticoincidence detectors. The large CsI crystal of CGRS has a higher detector effective area than other lunar gamma ray spectrometers.

Meng-Hua Zhu; Tao Ma; Jin Chang

2010-01-01

321

Molecular Characterization of the Salmonella enterica Serovar Typhi Vi-Typing Bacteriophage E1  

Microsoft Academic Search

Some bacteriophages target potentially pathogenic bacteria by exploiting surface-associated virulence fac- tors as receptors. For example, phage have been identified that exhibit specificity for Vi capsule producing Salmonella enterica serovar Typhi. Here we have characterized the Vi-associated E1-typing bacteriophage using a number of molecular approaches. The absolute requirement for Vi capsule expression for infectivity was demonstrated using different Vi-negative S.

Derek Pickard; Nicholas R. Thomson; Stephen Baker; John Wain; Mercedes Pardo; David Goulding; Nancy Hamlin; Jyoti Choudhary; J. Threfall; G. Dougan

2008-01-01

322

Mouse Spermatocytes Express CYP2E1 and Respond to Acrylamide Exposure  

PubMed Central

Metabolism of xenobiotics by cytochrome P450s (encoded by the CYP genes) often leads to bio-activation, producing reactive metabolites that interfere with cellular processes and cause DNA damage. In the testes, DNA damage induced by xenobiotics has been associated with impaired spermatogenesis and adverse effects on reproductive health. We previously reported that chronic exposure to the reproductive toxicant, acrylamide, produced high levels of DNA damage in spermatocytes of Swiss mice. CYP2E1 metabolises acrylamide to glycidamide, which, unlike acrylamide, readily forms adducts with DNA. Thus, to investigate the mechanisms of acrylamide toxicity in mouse male germ cells, we examined the expression of the CYP, CYP2E1, which metabolises acrylamide. Using Q-PCR and immunohistochemistry, we establish that CYP2E1 is expressed in germ cells, in particular in spermatocytes. Additionally, CYP2E1 gene expression was upregulated in these cells following in vitro acrylamide exposure (1 µM, 18 h). Spermatocytes were isolated and treated with 1 µM acrylamide or 0.5 µM glycidamide for 18 hours and the presence of DNA-adducts was investigated using the comet assay, modified to detect DNA-adducts. Both compounds produced significant levels of DNA damage in spermatocytes, with a greater response observed following glycidamide exposure. A modified comet assay indicated that direct adduction of DNA by glycidamide was a major source of DNA damage. Oxidative stress played a small role in eliciting this damage, as a relatively modest effect was found in a comet assay modified to detect oxidative adducts following glycidamide exposure, and glutathione levels remained unchanged following treatment with either compound. Our results indicate that the male germ line has the capacity to respond to xenobiotic exposure by inducing detoxifying enzymes, and the DNA damage elicited by acrylamide in male germ cells is likely due to the formation of glycidamide adducts.

Nixon, Belinda J.; Katen, Aimee L.; Stanger, Simone J.; Schjenken, John E.; Nixon, Brett; Roman, Shaun D.

2014-01-01

323

Contribution of CYP2E1 and CYP3A to acetaminophen reactive metabolite formation  

Microsoft Academic Search

Background: CYP2E1, 1A2, and 3A4 have all been implicated in the formation of N-acetyl-p-benzoquinone imine (NAPQI), the reactive intermediate of acetaminophen (INN, paracetamol), in studies in human liver microsomes and complementary deoxyribonucleic acid–expressed enzymes. However, recent pharmacokinetic evidence in humans has shown that the involvement of CYP1A2 is negligible in vivo. The purpose of this study was to evaluate the

Peter T. Manyike; Evan D. Kharasch; Thomas F. Kalhorn; John T. Slattery

2000-01-01

324

The effects of intraportal administration of prostaglandin E 1 on liver ischemia and hepatectomy in rats  

Microsoft Academic Search

:   The effects of intraportal administration of prostaglandin E1 (PGE1) on portal venous flow, hepatic arterial flow, peripheral tissue blood flow, and systemic arterial flow before and after\\u000a 60 min total liver ischemia followed by 70% partial hepatectomy in rats were investigated. Total liver ischemia was induced\\u000a by occluding the hepatoduodenal ligament for 60 min. PGE1 at a dose of

Mohammad Akram Hossain; Isao Hamamoto; Shoji Kobayashi; Takashi Maeba; Hajime Maeta

1998-01-01

325

Selective allylic hydroxylation of acyclic terpenoids by CYP154E1 from Thermobifida fusca YX  

PubMed Central

Summary Allylic alcohols are valuable precursors in the synthesis of pharmaceutical intermediates, agrochemicals and natural products. Regioselective oxidation of parental alkenes is a challenging task for chemical catalysts and requires several steps including protection and deprotection. Many cytochrome P450 enzymes are known to catalyse selective allylic hydroxylation under mild conditions. Here, we describe CYP154E1 from Thermobifida fusca YX that enables this type of oxidation. Several acyclic terpenoids were tested as possible substrates for CYP154E1, and the regio- and chemoselectivity of their oxidation was investigated. Using a previously established bioinformatics approach we identified position 286 in the active site of CYP154E1 which is putatively involved in substrate binding and thereby might have an effect on enzyme selectivity. To tune regio- and chemoselectivity of the enzyme three mutants at position 286 were constructed and used for substrate oxidation. All formed products were analysed with GC–MS and identified using chemically synthesised authentic samples and known compounds as references. Best regioselectivity towards geraniol and nerol was observed with the wild type enzyme mainly leading to 8-hydroxy derivatives (8-hydroxygeraniol or 8-hydroxynerol) with high selectivity (100% and 96% respectively). Highest selectivities during the oxidation of geranylacetone and nerylacetone were observed with the following variants: V286F led mainly to 7-hydroxygeranylacetone (60% of the total product) and V286A produced predominantly 12-hydroxynerylacetone (75% of total product). Thus, CYP154E1 and its mutants expand the tool-box for allylic hydroxylation in synthetic chemistry.

Kriening, Sebastian; Busch, Alexandrine; Seifert, Alexander; Pleiss, Jurgen; Laschat, Sabine

2014-01-01

326

Synthesis of colicin E1 in a cell-free coupled transcription-translation system  

Microsoft Academic Search

Protein was synthesized in a cell-free coupled transcription-translation (S30) system on plasmid Col E1 and phage T2 and Sd DNA templates. Phage T2 DNA and closed plasmid DNA proved to be the most active templates. The latter controlled the synthesis of eight individual proteinsin vitro, including the biologically active protein antibiotic colicin. The titer of colicin synthesized in this cell-free

V. V. Emel'yanov; V. N. Kalinin; B. M. Girdo; T. I. Tikhonenko

1976-01-01

327

Expression and epitope analysis of the major allergenic protein Fag e 1 from buckwheat  

Microsoft Academic Search

Seeds of common buckwheat (Fagopyrum esculentum) contain valuable nutritive substances but also allergenic proteins that cause hypersensitive reactions. Thus, the development of hypoallergenic buckwheat would make this important pseudo-cereal available to allergic people. A major allergenic protein of buckwheat is Fag e 1. We isolated the respective cDNA, coding for a 22kDa protein, from a recently developed autogamous strain of

Hiroyuki Yoshioka; Tsuyoshi Ohmoto; Atsuo Urisu; Yoshinori Mine; Taiji Adachi

2004-01-01

328

Adenovirus E1A-mediated negative control of genes activated during F9 differentiation.  

PubMed

The phenotype of a differentiated cell results from the expression of a unique set of genes in that cell. The differentiation of F9 teratocarcinoma cells in response to retinoic acid and cyclic AMP is an excellent example of this process, as the appearance of several gene products during the course of the differentiation process has been documented. In principle, the activation of gene expression could be due to the appearance of positive-acting factors, the loss of negative-acting factors, or a combination of both. Since F9 cells have been shown to express a cellular E1A analog whereas differentiated F9 cells do not, and it is known that the viral E1A gene exerts a negative effect on transcription of both viral and cellular genes, we determined whether the cellular genes activated during F9 cell differentiation are subject to E1A negative control. We found that infection of differentiated F9 cells with wild-type adenovirus resulted in a decline in the levels of collagen type IV mRNA and plasminogen activator mRNA, both of which are induced by differentiation. At least for the collagen gene, this phenomenon appears to involve a transcriptional repression. PMID:2528683

Young, K S; Weigel, R; Hiebert, S; Nevins, J R

1989-07-01

329

Protective effect of liquiritigenin against methylglyoxal cytotoxicity in osteoblastic MC3T3-E1 cells.  

PubMed

Methylglyoxal (MG), a reactive dicarbonyl compound, is a metabolic byproduct of glycolysis and elevated MG levels contribute to diabetic complications. Glycation reactions of MG with amino acids can induce oxidative stress, leading to subsequent cytotoxicity. In the present study, the effect of liquiritigenin on MG-induced cytotoxicity was investigated using osteoblastic MC3T3-E1 cells. Pretreatment of MC3T3-E1 cells with liquiritigenin prevented the MG-induced cell death and production of protein adduct, intracellular reactive oxygen species, mitochondrial superoxide, cardiolipin peroxidation, and TNF-? in osteoblastic MC3T3-E1 cells. In addition, liquiritigenin increased the activity of glyoxalase I inhibited by MG. These findings suggest that liquiritigenin provides a protective action against MG-induced cell damage by reducing oxidative stress and by increasing MG detoxification. Pretreatment with liquiritigenin prior to MG exposure reduced MG-induced mitochondrial dysfunction by preventing mitochondrial membrane potential dissipation and adenosine triphosphate loss. Additionally, the nitric oxide and PGC-1? levels were significantly increased by liquiritigenin, suggesting that liquiritigenin may induce mitochondrial biogenesis. Our findings indicate that liquiritigenin might exert its therapeutic effects via enhancement of glyoxalase I activity and mitochondrial function, and anti-oxidant and anti-inflammatory activities. Taken together, liquiritigenin has potential as a preventive agent against the development of diabetic osteopathy related to MG-induced oxidative stress in diabetes. PMID:24789098

Suh, Kwang Sik; Rhee, Sang Youl; Kim, Young Seol; Choi, Eun Mi

2014-06-25

330

Effects of 6-Hydroxyflavone on Osteoblast Differentiation in MC3T3-E1 Cells  

PubMed Central

Osteoblast differentiation plays an essential role in bone integrity. Isoflavones and some flavonoids are reported to have osteogenic activity and potentially possess the ability to treat osteoporosis. However, limited information concerning the osteogenic characteristics of hydroxyflavones is available. This study investigates the effects of various hydroxyflavones on osteoblast differentiation in MC3T3-E1 cells. The results showed that 6-hydroxyflavone (6-OH-F) and 7-hydroxyflavone (7-OH-F) stimulated ALP activity. However, baicalein and luteolin inhibited ALP activity and flavone showed no effect. Up to 50??M of each compound was used for cytotoxic effects study; flavone, 6-OH-F, and 7-OH-F had no cytotoxicity on MC3T3-E1 cells. Moreover, 6-OH-F activated AKT and serine/threonine kinases (also known as protein kinase B or PKB), extracellular signal-regulated kinases (ERK 1/2), and the c-Jun N-terminal kinase (JNK) signaling pathways. On the other hand, 7-OH-F promoted osteoblast differentiation mainly by activating ERK 1/ 2 signaling pathways. Finally, after 5 weeks of 6-OH-F induction, MC3T3-E1 cells showed a significant increase in the calcein staining intensity relative to merely visible mineralization observed in cells cultured in the osteogenic medium only. These results suggested that 6-OH-F could activate AKT, ERK 1/2, and JNK signaling pathways to effectively promote osteoblastic differentiation.

Wu, Yu-Wei; Yeh, Shauh-Der; Lin, Yu-Hsaing; Tsai, Yu-Hui

2014-01-01

331

A comparison of substrate dynamics in human CYP2E1 and CYP2A6.  

PubMed

Considering the dynamic nature of CYPs, methods that reveal information about substrate and enzyme dynamics are necessary to generate predictive models. To compare substrate dynamics in CYP2E1 and CYP2A6, intramolecular isotope effect experiments were conducted, using deuterium labeled substrates: o-xylene, m-xylene, p-xylene, 2,6-dimethylnaphthalene, and 4,4'-dimethylbiphenyl. Competitive intermolecular experiments were also conducted using d(0)- and d(6)-labeled p-xylene. Both CYP2E1 and CYP2A6 displayed full isotope effect expression for o-xylene oxidation and almost complete suppression for dimethylbiphenyl. Interestingly, (k(H)/k(D))(obs) for d(3)-p-xylene oxidation ((k(H)/k(D))(obs)=6.04 and (k(H)/k(D))(obs)=5.53 for CYP2E1 and CYP2A6, respectively) was only slightly higher than (k(H)/k(D))(obs) for d(3)-dimethylnaphthalene ((k(H)/k(D))(obs)=5.50 and (k(H)/k(D))(obs)=4.96, respectively). One explanation is that in some instances (k(H)/k(D))(obs) values are generated by the presence of two substrates-bound simultaneously to the CYP. Speculatively, if this explanation is valid, then intramolecular isotope effect experiments should be useful in the mechanistic investigation of P450 cooperativity. PMID:17156750

Harrelson, John P; Henne, Kirk R; Alonso, Darwin O V; Nelson, Sidney D

2007-01-26

332

Bursts of energetic electron induced large surface charging observed by Chang'E-1  

NASA Astrophysics Data System (ADS)

A relationship between surface charging and bursts of energetic electron (BEE) event is presented in this paper. In a 200 km lunar polar orbit, during quiet time, 0.1-2.0 MeV BEE events were observed by High Energetic Particles Detectors (HPD) on board Chang'E-1, on December 22, 2007, when the spacecraft was within the inner terrestrial magnetosheath. At the same time, a large surface charging of ˜-5.4 kV was observed by Chang'E-1, which was evidenced by increasing the ions energy observed by Solar Wind Ion Detectors (SWIDs). We found that the surface charging is strongly correlated with BEE events, and the potentials of spacecraft surface charging was experientially expressed as U?3.6×10-5·fT (kV). The BEE events did occur in the solar wind, geomagnetic tail and magnetosheath alternately, whereas the surface charging during the BEE events is in the magnetosheath or transition region of boundaries. Though the observed surface charging was fewer than the BEE events, it is expected that the occurrence of the charging events caused by the bursts of energetic electrons should be more frequent than the Chang'E-1 observations. Meanwhile, the spacecraft charging indicates the lunar surface can be charged to negative kilovolt-scale by the BEE events even in quiet times.

Wang, X. Y.; Zhang, A. B.; Zhang, X. G.; Reme, H.; Kong, L. G.; Zhang, S. Y.; Yu, D. J.; Wang, S. J.; Zhu, G. W.

2012-10-01

333

Contribution of CYP2E1 polymorphism to aging in the mechanical workshop workers.  

PubMed

Aging is attributed to both genetic and environmental factors. Occupational exposure is one of the environmental factors with potential genotoxic effects. Researchers try to determine factors involved in genetic damages at hazards exposure that could accelerate aging. Cytochrome P450 2E1 (CYP2E1) gene contributes in activation and detoxification of the environmental hazards. This polymorphism plays an important role in susceptibility of inter-individuals to DNA damage at the occupational exposure. The current study evaluated the possible influence of this gene polymorphism in aging by genomic damages through the biomarkers alterations of micronuclei (MN), comet tail length and telomere length shortening at the exposure. In this study, buccal cells were collected from the oral cavity of exposed workers and non-exposed controls. The CYP2E1 genotypes were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The wild genotype significantly affected MN frequency (p?=?0.007) and relative telomere length (p?=?0.047) in the older group of workers. It was concluded that the interaction of gene polymorphism and exposure enhances DNA damage and accelerates aging consequently. PMID:23193996

Eshkoor, Sima Ataollahi; Ismail, Patimah; Rahman, Sabariah Abd; Adon, Mohd Yusoff; Devan, R Vasu

2013-05-01

334

Effects of 6-Hydroxyflavone on Osteoblast Differentiation in MC3T3-E1 Cells.  

PubMed

Osteoblast differentiation plays an essential role in bone integrity. Isoflavones and some flavonoids are reported to have osteogenic activity and potentially possess the ability to treat osteoporosis. However, limited information concerning the osteogenic characteristics of hydroxyflavones is available. This study investigates the effects of various hydroxyflavones on osteoblast differentiation in MC3T3-E1 cells. The results showed that 6-hydroxyflavone (6-OH-F) and 7-hydroxyflavone (7-OH-F) stimulated ALP activity. However, baicalein and luteolin inhibited ALP activity and flavone showed no effect. Up to 50? ? M of each compound was used for cytotoxic effects study; flavone, 6-OH-F, and 7-OH-F had no cytotoxicity on MC3T3-E1 cells. Moreover, 6-OH-F activated AKT and serine/threonine kinases (also known as protein kinase B or PKB), extracellular signal-regulated kinases (ERK 1/2), and the c-Jun N-terminal kinase (JNK) signaling pathways. On the other hand, 7-OH-F promoted osteoblast differentiation mainly by activating ERK 1/ 2 signaling pathways. Finally, after 5 weeks of 6-OH-F induction, MC3T3-E1 cells showed a significant increase in the calcein staining intensity relative to merely visible mineralization observed in cells cultured in the osteogenic medium only. These results suggested that 6-OH-F could activate AKT, ERK 1/2, and JNK signaling pathways to effectively promote osteoblastic differentiation. PMID:24795772

Lai, Chien-Hung; Wu, Yu-Wei; Yeh, Shauh-Der; Lin, Yu-Hsaing; Tsai, Yu-Hui

2014-01-01

335

Annealing mechanisms of self-interstitial related defect E1=Ec-0.39 eV in irradiated silicon  

NASA Astrophysics Data System (ADS)

DLTS and thermally stimulated capacitance (TSCap) studies of ?-particle irradiated p-Si were undertaken to obtain additional information about the self-interstitial related defect E1=Ec-0.39 eV. The E1 defect can be retained frozen up to room temperature without any minority carrier injection, but under injection conditions at 77-300 K the E1 becomes mobile. As a result of annealing of the E1 defect, the carbon interstitial concentration grows. The E1 defect production rate under reverse bias as well as thermal annealing behavior depends strongly on the temperature and impurity concentration. Numerical estimates of the E1 migration via a Bourgoin-Corbett mechanism are in good agreement with the experimental data obtained.

Abdullin, Kh. A.; Mukashev, B. N.

2012-07-01

336

Image-based strength assessment of bone.  

PubMed

A patient's bone status is commonly assessed by radiologic methods. Although the desired information concentrates on the probability of future fractures, the radiologic density is widely used as a surrogate for bone strength. There have been attempts to develop new parameters that have a closer relationship with bone strength, but the investigators tend to use a linear relationship between measured density and their strength-related parameter. We briefly discuss the background of mechanical deformation as it relates to bone and point out some of the basic principles involved in the assessment of strength. We then show that the relevant connection between strength and density makes use of the elastic modulus, which relates to density in a power law with an exponent of close to 2. We suggest modifications of some of the widely used strength-related parameter expressions that follow the theory more closely and will, thus, have the potential to better reflect the patient's bone status. PMID:18002986

Hangartner, Thomas N

2007-01-01

337

Strength-based assessment in clinical practice.  

PubMed

Strength-based assessment can enhance clinical clarity, improve the range of information, and provide a more complete picture of clients and their circumstances. Deficit-oriented assessment has improved the assessment and treatment of a number of disorders but, at the same time, has created a negative bias, considered strengths as clinical peripheries or by-products, tended to reduce clients to diagnostic categories, and created a power differential, which could be counterproductive to clinical efficacy. Strength-based assessment explores weaknesses as well as strengths to effectively deal with problems. We present a number of strength-based strategies for use in clinical practice. These strategies, we hope, will help clinicians to operationalize how strengths and weaknesses reverberate and contribute to a client's psychological status, which is comprehensive and guards against negative bias. PMID:19294732

Rashid, Tayyab; Ostermann, Robert F

2009-05-01

338

Bovine Papilloma Virus (BPV)Encoded E1 Protein Contains Multiple Activities Required for BPV DNA Replication  

Microsoft Academic Search

Replication of bovine papilloma virus (BPV) DNA requires two virus-encoded proteins, E1 and E2, while all other proteins are supplied by the host cell. Here, we describe the isolation of the E1 protein and show that it is a multifunctional protein. Purified E1 protein was required for the in vitro replication of BPV origin-containing DNA by extracts of mouse cells,

Yeon-Soo Seo; Freidemann Muller; Monika Lusky; Jerard Hurwitz

1993-01-01

339

Recruitment of Replication Protein A by the Papillomavirus E1 Protein and Modulation by Single-Stranded DNA  

PubMed Central

With the exception of viral proteins E1 and E2, papillomaviruses depend heavily on host replication machinery for replication of their viral genome. E1 and E2 are known to recruit many of the necessary cellular replication factors to the viral origin of replication. Previously, we reported a physical interaction between E1 and the major human single-stranded DNA (ssDNA)-binding protein, replication protein A (RPA). E1 was determined to bind to the 70-kDa subunit of RPA, RPA70. In this study, using E1-affinity coprecipitation and enzyme-linked immunosorbent assay-based interaction assays, we show that E1 interacts with the major ssDNA-binding domain of RPA. Consistent with our previous report, no measurable interaction between E1 and the two smaller subunits of RPA was detected. The interaction of E1 with RPA was substantially inhibited by ssDNA. The extent of this inhibition was dependent on the length of the DNA. A 31-nucleotide (nt) oligonucleotide strongly inhibited the E1-RPA interaction, while a 16-nt oligonucleotide showed an intermediate level of inhibition. In contrast, a 10-nt oligonucleotide showed no observable effect on the E1-RPA interaction. This inhibition was not dependent on the sequence of the DNA. Furthermore, ssDNA also inhibited the interaction of RPA with papillomavirus E2, simian virus 40 T antigen, human polymerase alpha-primase, and p53. Taken together, our results suggest a potential role for ssDNA in modulating RPA-protein interactions, in particular, the RPA-E1 interactions during papillomavirus DNA replication. A model for recruitment of RPA by E1 during papillomavirus DNA replication is proposed.

Loo, Yueh-Ming; Melendy, Thomas

2004-01-01

340

Adaptive Mutations in Sindbis Virus E2 and Ross River Virus E1 That Allow Efficient Budding of Chimeric Viruses  

Microsoft Academic Search

Alphavirus glycoproteins E2 and E1 form a heterodimer that is required for virus assembly. We have studied adaptive mutations in E2 of Sindbis virus (SIN) and E1 of Ross River virus (RR) that allow these two glycoproteins to interact more efficiently in a chimeric virus that has SIN E2 but RR E1. These mutations include K129E, K131E, and V237F in

KYONGMIN HWANG KIM; ELLEN G. STRAUSS; JAMES H. STRAUSS

2000-01-01

341

Resolvin E1 Regulates Inflammation at the Cellular and Tissue Level and Restores Tissue Homeostasis In Vivo1  

Microsoft Academic Search

Resolvin E1 (RvE1) is a potent proresolving mediator of inflammation derived from omega-3 eicosapentaenoic acid that acts locally to stop leukocyte recruitment and promote resolution. RvE1 displays potent counter-regulatory and tissue-protective actions in vitro and in vivo. Periodontal disease is a local inflammatory disease initiated by bacteria characterized by neutrophil- mediated tissue injury followed by development of a chronic immune

Hatice Hasturk; Alpdogan Kantarci; Emilie Goguet-Surmenian; Amanda Blackwood; Chris Andry; Charles N. Serhan; Thomas E. Van Dyke

342

Functional and evolutionary insight from the crystal structure of rubella virus protein E1.  

PubMed

Little is known about the three-dimensional organization of rubella virus, which causes a relatively mild measles-like disease in children but leads to serious congenital health problems when contracted in utero. Although rubella virus belongs to the same family as the mosquito-borne alphaviruses, in many respects it is more similar to other aerosol-transmitted human viruses such as the agents of measles and mumps. Although the use of the triple MMR (measles, mumps and rubella) live vaccine has limited its incidence in western countries, congenital rubella syndrome remains an important health problem in the developing world. Here we report the 1.8?Å resolution crystal structure of envelope glycoprotein E1, the main antigen and sole target of neutralizing antibodies against rubella virus. E1 is the main player during entry into target cells owing to its receptor-binding and membrane-fusion functions. The structure reveals the epitope and the neutralization mechanism of an important category of protecting antibodies against rubella infection. It also shows that rubella virus E1 is a class II fusion protein, which had hitherto only been structurally characterized for the arthropod-borne alphaviruses and flaviviruses. In addition, rubella virus E1 has an extensive membrane-fusion surface that includes a metal site, reminiscent of the T-cell immunoglobulin and mucin family of cellular proteins that bind phosphatidylserine lipids at the plasma membrane of cells undergoing apoptosis. Such features have not been seen in any fusion protein crystallized so far. Structural comparisons show that the class II fusion proteins from alphaviruses and flaviviruses, despite belonging to different virus families, are closer to each other than they are to rubella virus E1. This suggests that the constraints on arboviruses imposed by alternating cycles between vertebrates and arthropods resulted in more conservative evolution. By contrast, in the absence of this constraint, the strictly human rubella virus seems to have drifted considerably into a unique niche as sole member of the Rubivirus genus. PMID:23292515

DuBois, Rebecca M; Vaney, Marie-Christine; Tortorici, M Alejandra; Kurdi, Rana Al; Barba-Spaeth, Giovanna; Krey, Thomas; Rey, Félix A

2013-01-24

343

Age and Sex Differences in Orofacial Strength  

Microsoft Academic Search

This study explored age- and sex-related differences in orofacial strength. Healthy adult men (N = 88) and women (N = 83) participated in the study. Strength measures were obtained using the Iowa Oral Performance Instrument (IOPI). Anterior\\u000a and posterior tongue elevation strength measures were obtained using a standard method. Tongue protrusion and lateralization,\\u000a cheek compression, and lip compression measures utilized adaptors allowing the participant

Heather M. ClarkNancy; Nancy Pearl Solomon

344

Shear strength of mineral filter cakes  

Microsoft Academic Search

This study covers the shear strength measurements of very fine pressure filter cakes of TiO2, calcite fractions, labosil, kaolin and synthetically prepared glass spheres. The shear strength behavior of all these cakes at the full range of saturation, i.e. from S=0.0 to S=1.0, showed the same tendency as in the case of Schubert's diagram for the tensile strength of the

M. Ruhland; W. Stahl

2000-01-01

345

Shear Strength Criteria for Unsaturated Soils  

Microsoft Academic Search

Shear strength is one of the fundamental properties of unsaturated soils. It has been found to change with matric suction.\\u000a Various shear strength equations have been proposed for predicting the shear strength versus suction relationship for unsaturated\\u000a soils. Some of these equations are based on regression analysis of experimental data, while some are embodied in more complex\\u000a stress–strain constitutive models.

Daichao Sheng; Annan Zhou; Delwyn G. Fredlund

2011-01-01

346

Shear strength of reinforced geosynthetic clay liner  

Microsoft Academic Search

Direct shear tests are conducted to evaluate the internal strength of a reinforced geosynthetic clay liner (GCL) at normal stresses between 3.45 and 69.0 kPa. The polypropylene reinforcement increases the peak internal strength compared to that reported in the literature for unreinforced GCLs; however, the reinforced GCL exhibits a postpeak reduction in strength with displacement due to failure of the

Robert B. Gilbert; Federico Fernandez; David W. Horsfield

1996-01-01

347

Modeling the development of strength in pellets  

NASA Astrophysics Data System (ADS)

Mathematical models used for describing the heat hardening of iron-ore pellets should include a description of the development of fired strength. This paper reviews the mechanisms of strength development and presents a suitable formalism for strength development that can be used in mathematical models. The formalism is shown to adequately fit experimental results generated under laboratory conditions where the time-temperature profiles of the pellets are known.

Batterham, R. J.

1986-09-01

348

The drop in strength at cryogenic temperatures  

Microsoft Academic Search

1.Reduction of the ultimate strength with decreasing temperatures in fcc materials indicates embrittlement of the material.2.The reduction of the strength with decreasing temperature is due to the reduction of the effective surface energy, i.e., the increase of the resistance to plastic deformation with the occurrence of a crack at stresses close to the yield strength.3.The effect of stress concentrations on

D. V. Lebedev

1971-01-01

349

Structure of the pyruvate dehydrogenase multienzyme complex E1 component from Escherichia coli at 1.85 A resolution.  

PubMed

The crystal structure of the recombinant thiamin diphosphate-dependent E1 component from the Escherichia coli pyruvate dehydrogenase multienzyme complex (PDHc) has been determined at a resolution of 1.85 A. The E. coli PDHc E1 component E1p is a homodimeric enzyme and crystallizes with an intact dimer in an asymmetric unit. Each E1p subunit consists of three domains: N-terminal, middle, and C-terminal, with all having alpha/beta folds. The functional dimer contains two catalytic centers located at the interface between subunits. The ThDP cofactors are bound in the "V" conformation in clefts between the two subunits (binding involves the N-terminal and middle domains), and there is a common ThDP binding fold. The cofactors are completely buried, as only the C2 atoms are accessible from solution through the active site clefts. Significant structural differences are observed between individual domains of E1p relative to heterotetrameric multienzyme complex E1 components operating on branched chain substrates. These differences may be responsible for reported alternative E1p binding modes to E2 components within the respective complexes. This paper represents the first structural example of a functional pyruvate dehydrogenase E1p component from any species. It also provides the first representative example for the entire family of homodimeric (alpha2) E1 multienzyme complex components, and should serve as a model for this class of enzymes. PMID:11955070

Arjunan, Palaniappa; Nemeria, Natalia; Brunskill, Andrew; Chandrasekhar, Krishnamoorthy; Sax, Martin; Yan, Yan; Jordan, Frank; Guest, John R; Furey, William

2002-04-23

350

The E1 Protein of Human Papillomavirus Type 16 Is Dispensable for Maintenance Replication of the Viral Genome  

PubMed Central

Papillomavirus genomes are thought to be amplified to about 100 copies per cell soon after infection, maintained constant at this level in basal cells, and amplified for viral production upon keratinocyte differentiation. To determine the requirement for E1 in viral DNA replication at different stages, an E1-defective mutant of the human papillomavirus 16 (HPV16) genome featuring a translation termination mutation in the E1 gene was used. The ability of the mutant HPV16 genome to replicate as nuclear episomes was monitored with or without exogenous expression of E1. Unlike the wild-type genome, the E1-defective HPV16 genome became established in human keratinocytes only as episomes in the presence of exogenous E1 expression. Once established, it could replicate with the same efficiency as the wild-type genome, even after the exogenous E1 was removed. However, upon calcium-induced keratinocyte differentiation, once again amplification was dependent on exogenous E1. These results demonstrate that the E1 protein is dispensable for maintenance replication but not for initial and productive replication of HPV16.

Egawa, Nagayasu; Nakahara, Tomomi; Ohno, Shin-ichi; Narisawa-Saito, Mako; Yugawa, Takashi; Fujita, Masatoshi; Yamato, Kenji; Natori, Yukikazu

2012-01-01

351

Differential expression and sequence polymorphism of the olive pollen allergen Ole e 1 in two Iranian cultivars.  

PubMed

Molecular evidence on the heterogeneity present in the Ole e 1 allergen of the olive pollen is emerging. Such polymorphism is dependent on the cultivar origin of pollen, which also determines wide differences in the expression of this protein. Determination of biochemical and molecular characteristics of Ole e 1 pollen allergen in two Iranian olive cultivars, namely 'Rowghani' and 'Zard' is necessary to assess their allergenicity potential. SDS-PAGE and immunoblotting analysis of pollen extracts showed that both cultivars present high and low expression of Ole e 1, respectively. These protein levels correlated with similarly different levels of transcripts, as determined by RT-PCR. Two-dimensional protein profiles also showed conspicuous differences in the distribution and the level of expression of those spots reacting to an anti-Ole e 1 antibody. Bioinformatic analysis of four Ole e 1 sequences corresponding to 'Rowghani' and two sequences for 'Zard', showed numerous heterogeneities when compared with those Ole e 1 and Ole e 1-like sequences present in databases. Nucleotide substitutions resulted in many cases in changes over the predicted amino acid sequences. A cladistic analysis of the sequences showed Iranian entries in a central position between West-European sequences, and Ole e 1-like sequences from other Oleaceae species. Moreover, amino acid changes affected key epitopes of the protein involved in the recognition of the protein by the human immune system. Putative implications of polymorphism in both the biological role and the allergic reactivity of Ole e 1 are discussed. PMID:23454775

Soleimani, Ali; Morales, Sonia; Jimenez-Lopez, Jose Carlos; Castro, Antonio Jesús; Rodríguez-García, María Isabel; de Dios Alché, Juan

2013-03-01

352

The adenoviral E1A protein displaces corepressors and relieves gene repression by unliganded thyroid hormone receptors in vivo  

PubMed Central

The human adenovirus type 5 early region 1A (E1A) is one of two oncogenes present in the adenovirus genome and functions by interfering with the activities of cellular regulatory proteins. The E1A gene is alternatively spliced to yield five products. Earlier studies have revealed that E1A can regulate the function of thyroid hormone (T3) receptors (TRs). However, analysis in yeast compared to transfection studies in mammalian cell cultures yields surprisingly different effects. Here, we have examined the effect of E1A on TR function by using the frog oocyte in vivo system, where the effects of E1A can be studied in the context of chromatin. We demonstrate that different isoforms of E1A have distinct effects on TR function. The two longest forms inhibit both the repression by unliganded TR and activation by T3-bound TR. We further show that E1A binds to unliganded TR to displace the endogenous corepressor N-CoR, thus relieving the repression by unliganded TR. On the other hand, in the presence of T3, E1A inhibits gene activation by T3-bound TR indirectly, through a mechanism that requires its binding domain for the general coactivator p300. Taken together, our results thus indicate that E1A affects TR function through distinct mechanisms that are dependent upon the presence or absence of T3.

Sato, Yukiyasu; Ding, Andrew; Heimeier, Rachel A.; Yousef, Ahmed S.; Mymryk, Joe S.; Walfish, Paul G.; Shi, Yun-Bo

2008-01-01

353

Characterization of papillomavirus E1 helicase mutants defective for interaction with the SUMO-conjugating enzyme Ubc9  

SciTech Connect

The E1 helicase from BPV and HPV16 interacts with Ubc9 to facilitate viral genome replication. We report that HPV11 E1 also interacts with Ubc9 in vitro and in the yeast two-hybrid system. Residues in E1 involved in oligomerization (353-435) were sufficient for binding to Ubc9 in vitro, but the origin-binding and ATPase domains were additionally required in yeast. Nuclear accumulation of BPV E1 was shown previously to depend on its interaction with Ubc9 and sumoylation on lysine 514. In contrast, HPV11 and HPV16 E1 mutants defective for Ubc9 binding remained nuclear even when the SUMO pathway was inhibited. Furthermore, we found that K514 in BPV E1 and the analogous K559 in HPV11 E1 are not essential for nuclear accumulation of E1. These results suggest that the interaction of E1 with Ubc9 is not essential for its nuclear accumulation but, rather, depends on its oligomerization and binding to DNA and ATP.

Fradet-Turcotte, Amelie [Laboratory of Molecular Virology, Institut de Recherches Cliniques de Montreal and Department of Biochemistry, University of Montreal, 110 Pine Avenue West, Montreal, Quebec, H2W 1R7 (Canada); Brault, Karine; Titolo, Steve [Department of Biological Sciences, Boehringer Ingelheim (Canada) Ltd., Laval, Quebec, H7S 2G5 (Canada); Howley, Peter M. [Department of Pathology, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115 (United States); Archambault, Jacques, E-mail: jacques.archambault@ircm.qc.c [Laboratory of Molecular Virology, Institut de Recherches Cliniques de Montreal and Department of Biochemistry, University of Montreal, 110 Pine Avenue West, Montreal, Quebec, H2W 1R7 (Canada)

2009-12-20

354

Correlated Strength in the Nuclear Spectral Function  

SciTech Connect

We have carried out an (e,ep) experiment at high momentum transfer and in parallel kinematics to measure the strength of the nuclear spectral function S(k,E) at high nucleon momenta k and large removal energies E. This strength is related to the presence of short-range and tensor correlations, and was known hitherto only indirectly and with considerable uncertainty from the lack of strength in the independent-particle region. This experiment locates by direct measurement the correlated strength predicted by theory.

D. Rohe; C. S. Armstrong; R. Asaturyan; O. K. Baker; S. Bueltmann; C. Carasco; D. Day; R. Ent; H. C. Fenker; K. Garrow; A. Gasparian; P. Gueye; M. Hauger; A. Honegger; J. Jourdan; C. E. Keppel; G. Kubon; R. Lindgren; A. Lung; D. J. Mack; J. H. Mitchell; H. Mkrtchyan; D. Mocelj; K. Normand; T. Petitjean; O. Rondon; E. Segbefia; I. Sick; S. Stepanyan; L. Tang; F. Tiefenbacher; W. F. Vulcan; G. Warren; S. A. Wood; L. Yuan; M. Zeier; H. Zhu; B. Zihlmann

2004-10-01

355

Analysis on collapse strength of casing wear  

NASA Astrophysics Data System (ADS)

Carrying capacity of the casing will reduce after the casing is worn, which seriously affects the subsequent well drilling, well completion, oil extraction and well repair. A lot of researches on calculation of casing wear collapse strength have been done, but few of them focus on collapsing failure mechanism, and influencing factors and law of collapse strength. So, significant difference between estimated value and actual value of collapse strength comes into being. By theoretical analysis, numerical simulation and actual test, the collapsing failure mechanism of casing wear as well as the influencing factors and laws of collapse strength are investigated, and the investigation results show that collapse of crescent casing wear belongs to "three hinged" instability. The severely-worn position on the casing is yielded into the plastic zone first then deformed greatly, which causes the plastic instability of the whole structure. The casing wear collapse strength presents changes of exponent, power function and linear trend with the residual casing wall thickness, wear radius and axial load, respectively. When the flexibility is less than 10°/30 m, the borehole bending has less impact on casing collapse strength. Thus, the computation model for the casing wear collapsing strength is established by introducing wear radius coefficient and casing equivalent yield strength, at the same time, the model is tested. The test results show that the relative error for the computation model is less than 5%. The research results provide a basis for design of the casing string strength and evaluation of down-hole safety.

Liang, Erguo; Li, Zifeng; Han, Yong; Li, Guoqin; Guo, Peipei

2013-05-01

356

Correlated strength in the nuclear spectral function.  

PubMed

We have carried out an (e,e'p) experiment at high momentum transfer and in parallel kinematics to measure the strength of the nuclear spectral function S(k,E) at high nucleon momenta k and large removal energies E. This strength is related to the presence of short-range and tensor correlations, and was known hitherto only indirectly and with considerable uncertainty from the lack of strength in the independent-particle region. This experiment locates by direct measurement the correlated strength predicted by theory. PMID:15525158

Rohe, D; Armstrong, C S; Asaturyan, R; Baker, O K; Bueltmann, S; Carasco, C; Day, D; Ent, R; Fenker, H C; Garrow, K; Gasparian, A; Gueye, P; Hauger, M; Honegger, A; Jourdan, J; Keppel, C E; Kubon, G; Lindgren, R; Lung, A; Mack, D J; Mitchell, J H; Mkrtchyan, H; Mocelj, D; Normand, K; Petitjean, T; Rondon, O; Segbefia, E; Sick, I; Stepanyan, S; Tang, L; Tiefenbacher, F; Vulcan, W F; Warren, G; Wood, S A; Yuan, L; Zeier, M; Zhu, H; Zihlmann, B

2004-10-29

357

Mechanical strength and stability of lithium aluminate  

NASA Astrophysics Data System (ADS)

Pacific Northwest Laboratory (PNL) investigated the strength and resistance to thermal shock of lithium aluminate annular pellets. The room temperature, axial compressive fracture strength of pellets made at Westinghouse Advanced Energy Systems (WAES) varied from 80 to 133 ksi. The strength at 430 C (806 F) was to 30 to 40 percent lower. The strength at 900 C (1652 F) showed a wide variation with one measurement near 90 ksi. These strength values are consistent with other data and predictions made in the literature when the grain size and porosity of the microstructure are taken into account. In diametral compression tests, the fracture strengths were much lower due to the existence of tensile stresses in some pellet regions from this type of loading. However, the fracture stresses were still generally higher than those reported in the literature; this fracture resistance probably reflects the better quality of the pellets tested in this study. Measurements on pellets made at PNL indicated lower strengths compared to the WAES material. This strength difference could be accounted for by different processing technologies: material made at PNL was cold-pressed and sintered with high porosity whereas the WAES material was isostatically hot-pressed with high density. Thermal shocking of the material by ramping to 900 C in two minutes did not have an observable effect on the microstructure or the strength of any of the pellets.

Brimhall, J. L.

1992-06-01

358

Accelerated Strength Testing of Thermoplastic Composites  

NASA Technical Reports Server (NTRS)

Constant ramp strength tests on unidirectional thermoplastic composite specimens oriented in the 90 deg. direction were conducted at constant temperatures ranging from 149 C to 232 C. Ramp rates spanning 5 orders of magnitude were tested so that failures occurred in the range from 0.5 sec. to 24 hrs. (0.5 to 100,000 MPa/sec). Below 204 C, time-temperature superposition held allowing strength at longer times to be estimated from strength tests at shorter times but higher temperatures. The data indicated that a 50% drop in strength might be expected for this material when the test time is increased by 9 orders of magnitude. The shift factors derived from compliance data applied well to the strength results. To explain the link between compliance and strength, a viscoelastic fracture model was investigated. The model, which used compliance as input, was found to fit the strength data only if the critical fracture energy was allowed to vary with temperature reduced stress rate. This variation in the critical parameter severely limits its use in developing a robust time-dependent strength model. The significance of this research is therefore seen as providing both the indication that a more versatile acceleration method for strength can be developed and the evidence that such a method is needed.

Reeder, J. R.; Allen, D. H.; Bradley, W. L.

1998-01-01

359

Interaction of Adenovirus E1A with the HHV8 Promoter of Latent Genes: E1A Proteins are Able to Activate the HHV-8 LANAp in MV3 Reporter Cells  

PubMed Central

Human herpesvirus 8 (HHV-8) is associated with Kaposi’s sarcoma, body cavity-based lymphoma, and Castleman’s disease. Adenoviral (Ad) E1A proteins regulate the activity of cellular and viral promoters/enhancers and transcription factors and can suppress tumorigenicity of human cancers. As (i) HHV-8 and Ad may co-exist in immunocompromised patients and (ii) E1A might be considered as therapeutic transgene for HHV-8-associated neoplasms we investigated whether the promoter of the latency-associated nuclear antigen (LANAp) controlling expression of vCyclin, vFLIP, and LANA proteins required for latent type infection is regulated by E1A. Transfection experiments in MV3 melanoma cells revealed activation of the LANAp by Ad5 E1A constructs containing an intact N terminus (aa 1-119). In particular, an Ad12 E1A mutant, Spm2, lacking six consecutive alanine residues in the “spacer” region activated the HHV-8 promoter about 15-fold compared to vector controls. In summary, we report the activation of the LANAp by E1A as a novel interaction of E1A with a viral promoter. These data may have relevance for the management of viral infections in immunocompromised patients. A role for E1A as a therapeutic in this context remains to be defined.

Koehler-Hansner, Karin; Flore, Ornella; Opalka, Bertram; Hengge, Ulrich R

2008-01-01

360

Interaction of Adenovirus E1A with the HHV8 Promoter of Latent Genes: E1A Proteins are Able to Activate the HHV-8 LANAp in MV3 Reporter Cells.  

PubMed

Human herpesvirus 8 (HHV-8) is associated with Kaposi's sarcoma, body cavity-based lymphoma, and Castleman's disease. Adenoviral (Ad) E1A proteins regulate the activity of cellular and viral promoters/enhancers and transcription factors and can suppress tumorigenicity of human cancers. As (i) HHV-8 and Ad may co-exist in immunocompromised patients and (ii) E1A might be considered as therapeutic transgene for HHV-8-associated neoplasms we investigated whether the promoter of the latency-associated nuclear antigen (LANAp) controlling expression of vCyclin, vFLIP, and LANA proteins required for latent type infection is regulated by E1A. Transfection experiments in MV3 melanoma cells revealed activation of the LANAp by Ad5 E1A constructs containing an intact N terminus (aa 1-119). In particular, an Ad12 E1A mutant, Spm2, lacking six consecutive alanine residues in the "spacer" region activated the HHV-8 promoter about 15-fold compared to vector controls. In summary, we report the activation of the LANAp by E1A as a novel interaction of E1A with a viral promoter. These data may have relevance for the management of viral infections in immunocompromised patients. A role for E1A as a therapeutic in this context remains to be defined. PMID:19440465

Koehler-Hansner, Karin; Flore, Ornella; Opalka, Bertram; Hengge, Ulrich R

2008-01-01

361

Recombinant human adenoviruses containing hybrid adenovirus type 5 (Ad5)/Ad12 E1A genes: characterization of hybrid E1A proteins and analysis of transforming activity and host range.  

PubMed Central

Hybrid adenovirus type 12 (Ad12)/Ad5 E1A genes were constructed by homologous recombination in Escherichia coli, a technique which offers several advantages over conventional mutagenesis for genetic analysis of proteins. In particular, functional differences between the proteins can be mapped by correlating the replacement of specific sequences with the acquisition of new properties, and there is no requirement for common unique restriction sites or polymerase chain reaction strategies to construct the hybrids. Recombinant adenoviruses expressing these hybrid E1A proteins were capable of replicating efficiently in HeLa cells, with the exception of one construct which contained a hybrid transactivation domain. The transforming activity of the hybrid E1A constructs was assayed by DNA transfection of primary baby rat kidney cells. Plasmids containing Ad12 E1 were approximately 20-fold less efficient at transformation than those with E1 of Ad5, and it was found that two regions in exon 1 of E1A mediate this difference. No differences were found in the abilities of any hybrid E1A proteins to bind to cellular proteins previously determined to be important for transformation by E1A. Images

Jelinek, T; Graham, F L

1992-01-01

362

Probabilistic Modeling of Ceramic Matrix Composite Strength  

NASA Technical Reports Server (NTRS)

Uncertainties associated with the primitive random variables such as manufacturing process (processing temperature, fiber volume ratio, void volume ratio), constituent properties (fiber, matrix and interface), and geometric parameters (ply thickness, interphase thickness) have been simulated to quantify the scatter in the first matrix cracking strength (FMCS) and the ultimate tensile strength of SCS-6/RBSN (SiC fiber (SCS-6) reinforced reaction-bonded silicon nitride composite) ceramic matrix composite laminate at room temperature. Cumulative probability distribution function for the FMCS and ultimate tensile strength at room temperature (RT) of (0)(sub 8), (0(sub 2)/90(sub 2), and (+/-45(sub 2))(sub S) laminates have been simulated and the sensitivity of primitive variables to the respective strengths have been quantified. Computationally predicted scatter of the strengths for a uniaxial laminate have been compared with those from limited experimental data. Also the experimental procedure used in the tests has been described briefly. Results show a very good agreement between the computational simulation and the experimental data. Dominating failure modes in (0)(sub 8), (0/90)(sub s) and (+/-45)(sub S) laminates have been identified. Results indicate that the first matrix cracking strength for the (0)(sub S), and (0/90)(sub S) laminates is sensitive to the thermal properties, modulus and strengths of both the fiber and matrix whereas the ultimate tensile strength is sensitive to the fiber strength and the fiber volume ratio. In the case of a (+/-45)(sub S), laminate, both the FMCS and the ultimate tensile strengths have a small scatter range and are sensitive to the fiber tensile strength as well as the fiber volume ratio.

Shan, Ashwin R.; Murthy, Pappu L. N.; Mital, Subodh K.; Bhatt, Ramakrishna T.

1998-01-01

363

Role for intestinal CYP2E1 in alcohol-induced circadian gene-mediated intestinal hyperpermeability  

PubMed Central

We have shown that alcohol increases Caco-2 intestinal epithelial cell monolayer permeability in vitro by inducing the expression of redox-sensitive circadian clock proteins CLOCK and PER2 and that these proteins are necessary for alcohol-induced hyperpermeability. We hypothesized that alcohol metabolism by intestinal Cytochrome P450 isoform 2E1 (CYP2E1) could alter circadian gene expression (Clock and Per2), resulting in alcohol-induced hyperpermeability. In vitro Caco-2 intestinal epithelial cells were exposed to alcohol, and CYP2E1 protein, activity, and mRNA were measured. CYP2E1 expression was knocked down via siRNA and alcohol-induced hyperpermeability, and CLOCK and PER2 protein expression were measured. Caco-2 cells were also treated with alcohol or H2O2 with or without N-acetylcysteine (NAC) anti-oxidant, and CLOCK and PER2 proteins were measured at 4 or 2 h. In vivo Cyp2e1 protein and mRNA were also measured in colon tissue from alcohol-fed mice. Alcohol increased CYP2E1 protein by 93% and enzyme activity by 69% in intestinal cells in vitro. Alcohol feeding also increased mouse colonic Cyp2e1 protein by 73%. mRNA levels of Cyp2e1 were not changed by alcohol in vitro or in mouse intestine. siRNA knockdown of CYP2E1 in Caco-2 cells prevented alcohol-induced hyperpermeability and induction of CLOCK and PER2 proteins. Alcohol-induced and H2O2-induced increases in intestinal cell CLOCK and PER2 were significantly inhibited by treatment with NAC. We concluded that our data support a novel role for intestinal CYP2E1 in alcohol-induced intestinal hyperpermeability via a mechanism involving CYP2E1-dependent induction of oxidative stress and upregulation of circadian clock proteins CLOCK and PER2.

Voigt, Robin M.; Shaikh, Maliha; Tang, Yueming; Cederbaum, Arthur I.; Turek, Fred W.; Keshavarzian, Ali

2013-01-01

364

The acute effects intensity and volume of strength training on running performance.  

PubMed

Strength training has been shown to cause acute detrimental effects on running performance. However, there is limited investigation on the effect of various strength training variables, whilst controlling eccentric contraction velocity, on running performance. The present study examined the effects of intensity and volume (i.e. whole body vs. lower body only) of strength training with slow eccentric contractions on running economy (RE) [i.e. below anaerobic threshold (AT)] and time-to-exhaustion (TTE) (i.e. above AT) 6 hours post. Fifteen trained and moderately endurance trained male runners undertook high-intensity whole body (HW), high-intensity lower body only (HL) and low-intensity whole body (LW) strength training sessions with slow eccentric contractions (i.e. 1:4 second concentric-to-eccentric contraction) in random order. Six hours following each strength training session, a RE test with TTE was conducted. The results showed that HW, HL and LW sessions had no effect on RE and that LW session had no effect on TTE (P ? 0.05). However, HW and HL sessions significantly reduced TTE (P < 0.05). These findings demonstrate that a 6-hour recovery period following HW, HL and LW sessions may minimize attenuation in endurance training performance below AT, although caution should be taken for endurance training sessions above AT amongst trained and moderately endurance trained runners. PMID:24533516

Doma, Kenji; Deakin, Glen Bede

2014-01-01

365

Organization of the transcriptional control region of the E1b gene of adenovirus type 5.  

PubMed Central

Genetic analysis of the transcriptional control sequences of the E1b gene of adenovirus type 5 identified two regions that stimulated specific transcription by whole cell extracts from uninfected cells. The first region, located within 50 nucleotides (position -50) 5' to the transcription initiation (cap) site, contains a G+C-rich consensus-binding site (GC box) for the transcription factor Sp1 and a TATA box. Unambiguous stimulatory activity of the second region, between positions -358 and -127, was observed only in the absence of the GC box. DNase I protection experiments (footprinting) with crude nuclear extracts from uninfected cells revealed multiple DNA-protein interactions at the control region. Proximal to the initiation site, both the GC box and the cap site were protected; however, protection of the TATA box was not observed. In the distal region, four protein-binding sites, designated I through IV, were located between positions -250 and -120. Three of the four mapped in protein-coding sequences of the adjacent E1a gene. Sites I and II were 5' to position -218 whereas sites III and IV were 3' to position -218. This finding was consistent with results of the transcriptional analysis indicating that subsets of the distal region were sufficient for stimulation of transcription in vitro in the absence of the GC box. Within the boundaries of site I, a 10-base-pair protected sequence was similar to one located 5' to the adenovirus E1a, E2a, E3, E4, E2 late, and polypeptide IX transcription initiation sites. Sequences within the boundaries of the other three sites were similar to those within other viral and cellular enhancers. Images

Parks, C L; Banerjee, S; Spector, D J

1988-01-01

366

TOLFENAMIC ACID SUPPRESSES CYTOCHROME P450 2E1 EXPRESSION IN MOUSE LIVER  

PubMed Central

Non-steroidal anti-inflammatory drugs (NSAIDs) play a significant role in the chemoprevention of cancer. We recently showed the chemopreventive response of a NSAID, 2-[(3-chloro-2- methylphenyl)amino]benzoic acid) known as tolfenamic acid (TA) in N-nitrosomethylbenzylamine (NMBA)-induced esophageal tumors in rats. Pre-clinical studies showed that TA inhibits Specificity protein (Sp) transcription factors and acts as an anti-cancer agent in several cancer models; however the pertinent mechanisms associated with its chemopreventive response in esophageal cancer are not known. Since the bioactivation of carcinogens through cytochrome P450 (CYP) is critical for the induction of cancer, we have studied the effect of TA on critical CYP isozymes in mouse liver samples. Athymic nude mice were treated with vehicle (corn oil) or TA (50mg/kg 3 times/wk) for 4 weeks. Protein extracts (whole cell lysates and microsomal fractions) were prepared from liver tissue and the expression of various CYP isozymes was determined by Western blot analysis. Rat (Sprague-Dawley) livers were harvested and primary hepatocyte cultures were treated with vehicle (DMSO) or TA (50 ?M) and cell viability was assessed at 2 and 5 days post-treatment. TA caused remarkable decrease in the expression of CYP2E1 in both liver lysates and sub-cellular fraction, while its response on other tested isozymes was marginal. TA did not affect the body weight of animals (mice) and viability of rat hepatocytes. These results demonstrate that TA modulates the expression of CYP2E1 which is associated with the bioactivation of carcinogens without causing apparent toxicity. These data suggest that TA-induced inhibition of CYP2E1 attenuates the bioactivation of carcinogens potentially leading to the chemoprevention of NMBA-induced esophageal tumorigenesis in rats.

Shukoor, Mohammed I.; Tiwari, Samata; Sankpal, Umesh T.; Maliakal, Pius; Connelly, Sarah F.; Siddiqi, Shaila; Siddiqi, Shadab A.; Basha, Riyaz

2012-01-01

367

Intestinal toxicity of acrylonitrile: in vitro metabolism by intestinal cytochrome P450 2E1.  

PubMed

Acrylonitrile (VCN) is known to cause extensive gastrointestinal damage and tumors in rats. In this study the metabolism of VCN to cyanide (CN-) was characterized in the small intestinal mucosa. The majority of the metabolic reactivity was localized in the microsomal fraction and required reduced nicotinamide adenine dinucleotide phosphate for maximal activity. The intestinal metabolism of VCN to CN- was characterized with respect to VCN concentration, time, pH, and microsomal protein concentration. VCN metabolism to CN- was enhanced significantly by the addition of sulfhydryl compounds such as glutathione, cysteine, and D-penicillamine (10 mM) to 142, 161, and 189% of control, respectively. The intestinal bioactivation of VCN to CN- was enhanced by microsomes obtained from intestinal mucosa of phenobarbital (455% of control), beta-naphthoflavone (375% of control), 4-methylpyrazole (305% of control), or ethanol (165% of control)-treated rats. Addition of ethanol (80 mM) to incubation mixtures containing control or ethanol-induced microsomes resulted in significant inhibition of microsomal metabolism of VCN to CN- to 20 and 34% of control, respectively. Addition of dimethyl sulfoxide induced a similar inhibitory effect on VCN metabolism by control or ethanol-induced microsomes (8 and 26% of control, respectively). Furthermore, antibody to cytochrome P450 2E1, but not antibody to cyt P450 2B1, significantly inhibited VCN metabolism by ethanol-induced intestinal microsomes to about 25% of control. Mild inhibition (80-85% of control) of VCN metabolism was detected when antibody to cyt P450 2B1 or 2E1 was added to incubation mixtures containing Pb-induced intestinal microsomes. These findings indicate that extrahepatic tissues such as the intestinal mucosa are capable of metabolizing VCN to CN- and establish a major role of intestinal cyt P450, particularly cyt P450 2E1, in the intestinal metabolism of VCN to CN-. PMID:7482528

Subramanian, U; Ahmed, A E

1995-11-01

368

Lysophosphatidic acid induces chemotaxis in MC3T3-E1 osteoblastic cells  

SciTech Connect

Lysophosphatidic acid (LPA) is a bioactive lipid that has pleiotropic effects on a variety of cell types and enhances the migration of endothelial and cancer cells, but it is not known if this lipid can alter osteoblast motility. We performed transwell migration assays using MC3T3-E1 osteoblastic cells and found LPA to be a potent chemotactic agent. Quantitative time-lapse video analysis of osteoblast migration after wounds were introduced into cell monolayers indicated that LPA stimulated both migration velocity and the average migration distance per cell. LPA also elicited substantial changes in cell shape and actin cytoskeletal structure; lipid-treated cells contained fewer stress fibers and displayed long membrane processes that were enriched in F-actin. Quantitative RT-PCR analysis showed that MC3T3-E1 cells express all four known LPA-specific G protein-coupled receptors (LPA1-LPA4) with a relative mRNA abundance of LPA1 > LPA4 > LPA2 >> LPA3. LPA-induced changes in osteoblast motility and morphology were antagonized by both pertussis toxin and Ki16425, a subtype-specific blocker of LPA1 and LPA3 receptor function. Cell migration in many cell types is linked to changes in intracellular Ca2+. Ki16425 also inhibited LPA-induced Ca2+ signaling in a dose-dependent manner, suggesting a link between LPA-induced Ca2+ transients and osteoblast chemotaxis. Our data show that LPA stimulates MC3T3-E1 osteoblast motility via a mechanism that is linked primarily to the G protein-coupled receptor LPA1.

Masiello, Lisa M.; Fotos, Joseph S.; Galileo, Deni S.; Karin, Norm J.

2006-07-01

369

Tolfenamic acid suppresses cytochrome P450 2E1 expression in mouse liver.  

PubMed

Non-steroidal anti-inflammatory drugs (NSAIDs) play a significant role in the chemoprevention of cancer. We recently showed the chemopreventive response of a NSAID, 2-[(3-chloro-2-methylphenyl)amino]benzoic acid) known as tolfenamic acid (TA) in N-nitrosomethylbenzylamine (NMBA)-induced esophageal tumors in rats. Pre-clinical studies showed that TA inhibits Specificity protein (Sp) transcription factors and acts as an anti-cancer agent in several cancer models; however the pertinent mechanisms associated with its chemopreventive response in esophageal cancer are not known. Since the bioactivation of carcinogens through cytochrome P450 (CYP) is critical for the induction of cancer, we have studied the effect of TA on critical CYP isozymes in mouse liver samples. Athymic nude mice were treated with vehicle (corn oil) or TA (50 mg kg(-1), 3 times per week) for 4 weeks. Protein extracts (whole cell lysates and microsomal fractions) were prepared from liver tissue and the expression of various CYP isozymes was determined by Western blot analysis. Rat (Sprague-Dawley) livers were harvested and primary hepatocyte cultures were treated with vehicle (DMSO) or TA (50 ?M) and cell viability was assessed at 2 and 5 days post-treatment. TA caused remarkable decrease in the expression of CYP2E1 in both liver lysates and sub-cellular fraction, while its response on other tested isozymes was marginal. TA did not affect the body weight of animals (mice) and viability of rat hepatocytes. These results demonstrate that TA modulates the expression of CYP2E1 which is associated with the bioactivation of carcinogens without causing apparent toxicity. These data suggest that TA-induced inhibition of CYP2E1 attenuates the bioactivation of carcinogens potentially leading to the chemoprevention of NMBA-induced esophageal tumorigenesis in rats. PMID:22832660

Shukoor, Mohammed I; Tiwari, Samata; Sankpal, Umesh T; Maliakal, Pius; Connelly, Sarah F; Siddiqi, Shaila; Siddiqi, Shadab A; Basha, Riyaz

2012-09-01

370

Calculation of energy levels, {ital E}1 transition amplitudes, and parity violation in francium  

SciTech Connect

Many-body perturbation theory in the screened Coulomb interaction was used to calculate energy levels, {ital E}1 trransition amplitudes, and the parity-nonconserving (PNC) {ital E}1 amplitude of the 7{ital s}-8{ital s} transition in francium. The method takes into account the core-polarization effect, the second-order correlations, and the three dominating sequences of higher-order correlation diagrams: screening of the electron-electron interaction, particle-hole interaction, and the iterations of the self-energy operator. The result for the PNC amplitude for {sup 223}Fr is {ital E}1(7{ital s}-8{ital s})=(1.59{plus_minus}{similar_to}1%){times}10{sup {minus}10}{ital iea}{sub {ital B}}({minus}{ital Q}{sub {ital W}}/{ital N}), where {ital Q}{sub {ital W}} is the weak charge of the nucleus, {ital N}=136 is the number of neutrons, {ital e}={vert_bar}{ital e}{vert_bar} is the elementary charge, and {ital a}{sub {ital B}} is the Bohr radius. Our prediction for the position of the 8{ital s} energy level of Fr, which has not been measured yet, is 13 110 cm{sup {minus}1} below the limit of the continuous spectrum. The accuracy of the calculations was controlled by comparison with available experimental data and analogous calculations for cesium. It is estimated to be {similar_to}0.1% for the energy levels and {similar_to}1% for the transition amplitudes.

Dzuba, V.A.; Flambaum, V.V.; Sushkov, O.P. [School of Physics, University of New South Wales, Sydney 2052 (Australia)] [School of Physics, University of New South Wales, Sydney 2052 (Australia)

1995-05-01

371

Phosphorylation of the adenovirus E1A-associated 300 kDa protein in response to retinoic acid and E1A during the differentiation of F9 cells.  

PubMed Central

Transcription of the c-jun gene is up-regulated by either retinoic acid (RA) or adenovirus E1A during the differentiation of F9 cells. We show here that RA and E1A induce phosphorylation of the E1A-associated 300 kDa protein (p300) during the differentiation of F9 cells. The region of E1A that is required for interaction with cellular protein p300 overlaps with the region of E1A required for E1A to induce expression of the c-jun gene. Treatment of F9 cells with RA or infection of the cells by adenovirus led to a decrease in the electrophoretic mobility of p300. Phosphatase treatment of p300 from RA-treated or adenovirus-infected F9 cells reversed the changes in migration of p300, indicating that RA- and E1A-mediated changes in the mobility of p300 were due to phosphorylation. We also found factors, designated DRF1 and DRF2, that bound specifically to a sequence element that is necessary and sufficient for RA- and E1A-mediated up-regulation of the c-jun gene. The mobility of DRF complexes was changed by E1A or RA and the complexes were supershifted by addition of a polyclonal p300 antiserum. Moreover, overexpression of p300 resulted in an increase in the level of DRF1 complex. p300 fused to the DNA binding domain of the E2 protein of papilloma virus stimulated E2-dependent reporter activity in response to RA or E1A in F9 cells. Our results suggest that p300 is part of the DRF complexes, that it is differentially phosphorylated in undifferentiated versus differentiated cells and that it is likely involved in regulating transcription of the c-jun gene during F9 cell differentiation. Images

Kitabayashi, I; Eckner, R; Arany, Z; Chiu, R; Gachelin, G; Livingston, D M; Yokoyama, K K

1995-01-01

372

The Strengths Perspective: Fortigenesis in Adult Life  

ERIC Educational Resources Information Center

"Fortigenesis" (L. fortis=strong) refers to a process of developing strengths at a variety of endpoints. Assumptions are: (i) there exist 2 continua, of mental illness and mental health, along which waxing and waning in the process of fortigenesis moves individuals in the directions of more or less strength; (ii) challenge, struggling and…

Strumpfer, D. J. W.

2006-01-01

373

The Strengths of Black Families Revisited.  

ERIC Educational Resources Information Center

Presents the "Strengths of Black Families" of R. B. Hill (1972) as a paradigm for understanding family behavior. Introduces the practice approach to these strengths in the work of E. Hall and G. King (1982) that is effective for developing family intervention strategies related to social and economic problems. (SLD)

Hudgins, John L.

1992-01-01

374

Threshold Tear Strength of some Molecular Networks.  

National Technical Information Service (NTIS)

The tear strength of polydimethylsiloxane (PDMS) networks was found to be only about one-third as large as that of polybutadiene (PB) or polyisoprene (PI) networks of similar M sub c when the tear strength was measured under threshold conditions, i.e., at...

A. N. Gent R. H. Tobias

1981-01-01

375

Static Material Strength Determined Using a DAC  

SciTech Connect

By measuring sample thickness and pressure gradient using x-ray absorption and x-ray diffraction, respectively, the accurate static yield strengths of Ta and Fe were determined at high pressure. This improved method has several advantages over other similar methods to quantitatively determine static material strength.

Cynn, H; Evans, W; Klepeis, J P; Lipp, M; Liermann, P; Yang, W

2009-06-04

376

Oblique impact simulations of high strength agglomerates  

Microsoft Academic Search

Different types of particle compounds like concrete particles can be considered as a model material of high strength agglomerates. It is necessary to investigate and understand fracture behaviour of these agglomerates in order to avoid breakage during storage, handling and transportation. The aim of the research is to examine the comminution behaviour of high strength agglomerates during oblique impact loadings.A

Manoj Khanal; Jürgen Tomas

2009-01-01

377

Strength and Fatigue Life of Wire Rope  

Microsoft Academic Search

A method is presented that predicts the fatigue life of a large diameter wire rope, from test data for small diameter rope. Dimensional analysis and the technique of interpolation and extrapolation are employed. The method is applied first to study size effects on the breaking strength of wire ropes and then to predict fatigue strength. Results are compared with experimental

Chi-Hui Chien; Raymond A. LeClair; George A. Costello

1988-01-01

378

Effects of Directional Exercise on Lingual Strength  

ERIC Educational Resources Information Center

Purpose: To examine the application of known muscle training principles to tongue strengthening exercises and to answer the following research questions: (a) Did lingual strength increase following 9 weeks of training? (b) Did training conducted using an exercise moving the tongue in one direction result in strength changes for tongue movements in…

Clark, Heather M.; O'Brien, Katy; Calleja, Aimee; Corrie, Sarah Newcomb

2009-01-01

379

Ceramic granule strength variability and compaction behavior.  

National Technical Information Service (NTIS)

Diametral compression strength distributions and the compaction behavior and of irregular shape 150--200 (mu)m ceramic granules and uniform-size 210 (mu)m glass spheres were measured to determine how granule strength variability relates to compaction beha...

S. J. Glass K. G. Ewsuk M. J. Readey

1995-01-01

380

Link Between Mixing Requirements and Dough Strength  

Microsoft Academic Search

Cereal Chem. 76(5):800-806 Industrial bakeries in Australia and New Zealand using the mechanical dough development (MDD) process have experienced undesirable increases in dough mixing requirements. This problem is an unwanted outcome of breeding programs that have endeavored to increase dough strength as a desirable characteristic. Research was undertaken to determine the nature of the link between dough strength and mixing

A. R. Wooding; S. Kavale; F. MacRitchie; F. L. Stoddard

1999-01-01

381

The Shear Strength of Thin Lubricant Films  

Microsoft Academic Search

This paper describes a study of the effects of pressure and temperature on the shear strength of very thin layers of a number of lubricants. The shear strength is deduced from measurements of the tangential (frictional) force required to slide glass spheres over glass plates coated with the lubricant. It is assumed that no glass-glass contact occurs through the lubricant

B. J. Briscoe; B. Scruton; F. R. Willis

1973-01-01

382

Normalized undrained shear strength of clay shales  

Microsoft Academic Search

This paper examines the possibility of normalizing the undrained shear strength behavior of clay shales. Shales are formed in sedimentary basins by diagenetic processes, which turn young clay sediments into compacted and lithified shales. Cementation at grain contacts affects many properties of shales including the apparent preconsolidation and shear strength. Based on a study of 25 different types of materials,

Marte Gutierrez; Runar Nygård; Kaare Høeg; Toralv Berre

2008-01-01

383

Strength Training, Not Only for the Young.  

ERIC Educational Resources Information Center

Research indicates that increased strength leads to improved balance and functional mobility and that nearly every senior patient can benefit from basic resistance training. The article provides guidelines for physicians on prescribing resistance training and for patients on increasing strength. (SM)

Munnings, Frances

1993-01-01

384

In situ Shear Strength Tester for Coal.  

National Technical Information Service (NTIS)

The objective of this research was to develop a device for rapid in situ measurement of rock shearing strength and to compare the shearing strength results with those obtained by other test methods. The rock borehole shear test (RBST) operates by expansio...

R. L. Handy L. E. Engle J. M. Pitt

1976-01-01

385

Maximal Strength Testing in Healthy Children.  

ERIC Educational Resources Information Center

Evaluated the safety and efficacy of 1 repetition maximum (1RM) strength testing in healthy children age 6-12 years. Data were collected on 96 children who performed a 1RM test on one upper body and one lower body exercise using child-sized weight machines. Findings indicated that children could safely perform 1RM strength tests provided…

Faigenbaum, Avery D.; Milliken, Laurie A.; Westcott, Wayne L.

2003-01-01

386

Effect of reinforcement corrosion on bond strength  

Microsoft Academic Search

The effect of reinforcement corrosion on the bond strength between steel and concrete was investigated. The bond behaviour of reinforced concrete elements, including the ultimate bond strength, free-end slip, and the modes of failure in precracking, cracking and postcracking stages was studied. Also, the effect of different crack widths and the rib profile degradation for various degrees of corrosion on

Abdullah A. Almusallam; Ahmad S. Al-Gahtani; Abdur Rauf Aziz; Rasheeduzzafar

1996-01-01

387

Cryogenic insulation strength and bond tester  

Microsoft Academic Search

A method and apparatus for testing the tensile strength and bonding strength of sprayed-on foam insulation attached to metal cryogenic fuel tanks. A circular cutter is used to cut the insulation down to the surface of the metal tank to form plugs of the insulation for testing ''in situ'' on the tank. The apparatus comprises an electro-mechanical pulling device powered

P. H. Schuerer; J. H. Ehl; W. P. Prasthofer

1985-01-01

388

Cryogenic Insulation Strength and Bond Tester.  

National Technical Information Service (NTIS)

A method and apparatus for testing the tensile strength and bonding strength of sprayed-on foam insulation attached to metal cryogenic fuel tanks is described. A circular cutter is used to cut the insulation down to the surface of the metal tank to form p...

P. H. Schuerer J. H. Ehl W. P. Prasthofer

1983-01-01

389

Tools for Building on Youth Strengths  

Microsoft Academic Search

While rhetoric about strength-based approaches abounds, this perspective has not penetrated the front lines of practice. Many programs serving troubled youngsters are still mired in a deficit and deviance orientation. This article provides practical strategies for assessing the strengths of children and developing interventions to tap their assets in achieving educational and treatment goals.

Kathy Cox

2008-01-01

390

Strength of Reinforced Aluminum-Base Composites.  

National Technical Information Service (NTIS)

The article discusses increasing the high-temperature strength of materials by a new method. Using high-strength fibers to reinforce results in high qualities of service not attained by previously known methods. This work studied the effect of reinforcing...

D. M. Karpinos G. G. Maksimovich V. K. Kadyrov E. M. Lyutyi I. Y. Tretyak

1974-01-01

391

Strength Development and Motor-Sports Improvement.  

ERIC Educational Resources Information Center

This document examines the effects of strength-development programs on the improvement of motor skills and sports competencies. Part one defines various terms used throughout the development studies. Part two discusses the mixed results of experiments involving speed of movement as the motor item indicative of strength development. Part three…

Clarke, H. Harrison, Ed.

1974-01-01

392

Determination of tensile strength of paraffin waxes  

Microsoft Academic Search

The tensile strength of paraffin wax is considered to be one of the important property indices that are used to characterize the service properties of this material. Methods used to determine the tensile strength of waxes are based on the use of Perkins and Tinius-Olsen testers [1]. Essentially, these methods consist of determinations of the force required to break a

O. G. Asadchii; B. Z. Votlokhin; N. F. Bogdanov; V. P. Gladyshev

1979-01-01

393

Strength enhancement process for prealloyed powder superalloys  

NASA Technical Reports Server (NTRS)

A technique involving superplastic processing and high pressure autoclaving was applied to a nickel base prealloyed powder alloy. Tensile strengths as high as 2865 MN/sq m at 480 C were obtained with as-superplastically deformed material. Appropriate treatments yielding materials with high temperature tensile and stress rupture strengths were also devised.

Waters, W. J.; Freche, J. C.

1977-01-01

394

Assessment of respiratory muscle function and strength  

Microsoft Academic Search

Measurement of respiratory muscle strength is useful in order to detect respiratory muscle weakness and to quantify its severity. In patients with severe respiratory muscle weakness, vital capacity is reduced but is a non-specific and relatively insensitive measure. Conventionally, inspiratory and expiratory muscle strength has been assessed by maximal inspiratory and expiratory mouth pressures sustained for 1 s (PImax and

N. Syabbalo

1998-01-01

395

Rest Interval between Sets in Strength Training  

Microsoft Academic Search

Strength training has become one of the most popular physical activities for increasing characteristics such as absolute muscular strength, endurance, hypertrophy and muscular power. For efficient, safe and effective training, it is of utmost importance to understand the interaction among training vari- ables, which might include the intensity, number of sets, rest interval between sets, exercise modality and velocity of

Belmiro Freitas de Salles; Roberto Simão; Fabrõ ´ cio Miranda; Jefferson da Silva Novaes; Adriana Lemos; Jeffrey M. Willardson

2009-01-01

396

Calculation of radiative corrections to E1 matrix elements in the neutral alkali metals  

SciTech Connect

Radiative corrections to E1 matrix elements for ns-np transitions in the alkali-metal atoms lithium through francium are evaluated. They are found to be small for the lighter alkali metals but significantly larger for the heavier alkali metals, and in the case of cesium much larger than the experimental accuracy. The relation of the matrix element calculation to a recent decay rate calculation for hydrogenic ions is discussed, and application of the method to parity nonconservation in cesium is described.

Sapirstein, J.; Cheng, K.T. [Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556 (United States); University of California, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

2005-02-01

397

E1 reaction-induced synthesis of hydrophilic oxide nanoparticles in a non-hydrophilic solvent  

NASA Astrophysics Data System (ADS)

In this paper, tert-amyl alcohol was employed to directly react with metal chlorides for the preparation of oxide nanoparticles. Some typical metal oxide or hydroxides with different morphologies, such as TiO2 nanoparticles, TiO2 nanorods, FeOOH nanowires, Fe2O3 nanoparticles, and SnO2 nanoparticles, can be easily fabricated through such simple chemical reactions. E1 reaction was found to play the leading role in the synthesis of metal oxides attributed to better stability of tertiary carbocations in tert-amyl alcohol and the strong interaction of metal chlorides with hydroxyl groups that results in the easy dissociation of carbon-oxygen bonds in tert-amyl alcohol. SN1 reaction can also occur in certain reactions due to nucleophilic substitution of chloride ions for hydroxyl groups. As-prepared metal oxides show good compatibility with an aqueous system while they were synthesized in a non-hydrophilic solvent probably attributed to the specific E1 reaction mechanism involving the generation of water, and can be directly incorporated into an aqueous soluble polymer, such as PVA, to exhibit many promising applications.In this paper, tert-amyl alcohol was employed to directly react with metal chlorides for the preparation of oxide nanoparticles. Some typical metal oxide or hydroxides with different morphologies, such as TiO2 nanoparticles, TiO2 nanorods, FeOOH nanowires, Fe2O3 nanoparticles, and SnO2 nanoparticles, can be easily fabricated through such simple chemical reactions. E1 reaction was found to play the leading role in the synthesis of metal oxides attributed to better stability of tertiary carbocations in tert-amyl alcohol and the strong interaction of metal chlorides with hydroxyl groups that results in the easy dissociation of carbon-oxygen bonds in tert-amyl alcohol. SN1 reaction can also occur in certain reactions due to nucleophilic substitution of chloride ions for hydroxyl groups. As-prepared metal oxides show good compatibility with an aqueous system while they were synthesized in a non-hydrophilic solvent probably attributed to the specific E1 reaction mechanism involving the generation of water, and can be directly incorporated into an aqueous soluble polymer, such as PVA, to exhibit many promising applications. Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr32255b

Hu, Ming-Jun; Gao, Jiefeng; Yang, Shiliu; Dong, Yucheng; Ping Wong, Julia Shuk; Xu, Jiaju; Shan, Guangcun; Li, Robert K. Y.

2012-09-01

398

Constrains on the Low-Energy e1 Cross Section of CARBON-12  

NASA Astrophysics Data System (ADS)

A substantially improved determination of the low-energy E1 amplitude of the ^{12 }C(alpha,gamma)^ {16}O reaction is reported, utilizing a precision measurement of the beta -delayed alpha-particle spectrum of ^{16}N. Radiative alpha capture on ^{12 }C is a key process occurring during helium burning in red giants. Its rate remains one of the most significant uncertainties in nucleosynthetic yield calculations for massive stars, with previous experimental determinations ranging over two orders of magnitude. This is largely due to the presence of subthreshold states in ^{16}O to which experimentally -accessible higher-energy data are only weakly sensitive. One of these, the E_{x} = 7.12 MeV l^-<=vel, has been predicted to have a considerable effect on the low-energy spectrum of alpha particles following the beta decay of ^{16 }N, in particular producing distinctive interference structure below the energy range of all previous experimental measurements. This new measurement can thus provide critical information to be used in the determination of the low -energy E1 cross section of ^{12}C( alpha,gamma)^{16}O. The ^{16}N betaalpha^ectrum has been measured down to an energy of E_{alpha } ~ 600 keV by detecting the alpha particles and recoiling ^ {12}C ions, in coincidence, in thin surface -barrier detectors. The ^{16} N nuclei were produced using the TRIUMF isotope separator TISOL. The coincidence technique allowed an exceptionally clean spectrum to be obtained; in particular, the tail of the detector response to higher-energy alpha particles could be clearly separated from the true low-energy events. The predicted low-energy interference structure was observed. The new spectrum, containing 10 ^6 counts, has been incorporated into K- and R-matrix analyses along with the previously measured ^{12}C(alpha, gamma)^{16}O cross section and ^{12}C+alpha elastic-scattering phase shifts. Best fit values for the E1 alpha-capture cross section at the energy most relevant to stellar helium burning, E_{alpha} = 300 keV, have been obtained. Expressed as an S factor they are S_{E1}(300) = 82 +/- 26 and 79 +/- 21 keV b for the K- and R-matrix parametrizations, respectively.

Powell, James David

1995-01-01

399

Observational Results of the ChangE-1 Solar X-Ray Monitor  

NASA Astrophysics Data System (ADS)

We present the primary observations of the Solar X-ray Monitor (SXM) payload onboard the ChangE-1 lunar exploration satellite, which was launched on 24 October 2007. The SXM payload uses a solid-state silicon P-I-N photo-diode (Si-PIN) whose dynamic energy ranges from 1 keV to 10 keV. The long-term integrated spectra at different solar-activity levels as observed by the SXM are presented. By fitting these spectra with an optically thin plasma model, the two-minute temperature variation of the solar coronal plasma during a solar flare is also presented.

Cui, X. Z.; Wang, H. Y.; Peng, W. X.; Zhang, C. M.; Liang, X. H.; Wang, J. Z.; Gao, M.; Yang, J. W.; Cao, X. L.; Zhang, J. Y.; Wu, M. Y.; Chang, J.; Sun, H. X.; OuYang, Z. Y.; Zhou, Y. L.; Li, C. L.

2013-12-01

400

Adenovirus 5 E1A enhances histone deacetylase inhibitors-induced apoptosis through Egr-1-mediated Bim upregulation  

PubMed Central

Histone deacetylase inhibitors (HDACi) are potent anti-cancer agents for variety of cancer types. Suberoylanilide hydroxamic acid (SAHA) has been approved as a drug to treat cutaneous T cell lymphoma, and the combination of HDACi and other agents have been actively tested in many clinical trials. Adenovirus 5 early region 1A (E1A) has been shown to exhibit high tumor suppressor activity, and gene therapy using E1A has been tested in clinical trials. Here, we showed that proapoptotic activity of HDACi was robustly enhanced by E1A in multiple cancer cells, but not in normal cells. Moreover, we showed that combination of E1A gene therapy and SAHA showed high therapeutic efficacy with low toxicity in vivo ovarian and breast xenograft models. SAHA downregulated Bcl-XL and upregulated proapoptotic BH3-only protein Bim, whose expression was further enhanced by E1A in cancer cells. These alterations of Bcl-2 family proteins were critical for apoptosis induced by the combination in cancer cells. SAHA enhanced acetylation of histone H3 in Bim promoter region, while E1A upregulated Egr-1, which was directly involved in Bim transactivation. Together, our results provide not only a novel insight into the mechanisms underlying anti-tumor activity of E1A, but also a rationale for the combined HDACi and E1A gene therapy in future clinical trials.

Yamaguchi, H; Chen, C-T; Chou, C-K; Pal, A; Bornmann, W; Hortobagyi, GN; Hung, M-C

2010-01-01

401

11 CFR 102.12 - Designation of principal campaign committee (2 U.S.C. 432(e) (1) and (3)).  

Code of Federal Regulations, 2011 CFR

...of principal campaign committee (2 U.S.C. 432(e) (1) and (3)). 102.12...RECORDKEEPING BY POLITICAL COMMITTEES (2 U.S.C. 433) § 102.12 Designation of principal campaign committee (2 U.S.C. 432(e) (1) and (3))....

2014-01-01

402

11 CFR 102.13 - Authorization of political committees (2 U.S.C. 432(e) (1) and (3)).  

Code of Federal Regulations, 2011 CFR

...Authorization of political committees (2 U.S.C. 432(e) (1) and (3)). 102.13...RECORDKEEPING BY POLITICAL COMMITTEES (2 U.S.C. 433) § 102.13 Authorization of political committees (2 U.S.C. 432(e) (1) and (3))....

2014-01-01

403

Partition of E1A proteins between soluble and structural fractions of adenovirus-infected and -transformed cells.  

PubMed Central

The partition of E1A proteins between soluble and structural framework fractions of human cells infected or transformed by subgroup C adenoviruses was investigated by using gentle cell fractionation conditions. A polyclonal antibody raised against a trpE-E1A fusion protein (K.R. Spindler, D.S.E. Rosser, and A. J. Berk, J. Virol. 132-141, 1984) synthesized in Escherichia coli was used to measure the steady-state levels of E1A proteins recovered in the various fractions by immunoblotting. The relative concentration of E1A proteins recovered in the soluble fraction of adenovirus type 2-infected cells was at least fivefold greater than the relative concentration in the corresponding fraction of transformed 293 cells. The observed distribution of E1A proteins was not altered by the sulfhydryl-blocking reagent N-ethylmaleimide. E1A proteins were recovered in nuclear matrix, chromatin, and cytoskeleton fractions after further fractionation of the structural framework fraction. However, the E1A protein species that could be identified by one-dimensional gel electrophoresis were not uniformly distributed among the subcellular fractions examined. The results obtained when fractionation was performed in the presence of the oxidation catalysts Cu2+ or (ortho-phenanthroline)2 Cu2+ indicate that E1A proteins can be efficiently cross-linked, via disulfide bonds, to the structural framework of both adenovirus-infected and adenovirus-transformed cells. Images

Chatterjee, P K; Flint, S J

1986-01-01

404

Hypergeometric Solutions for the q-Painlevé Equation of Type {E^{(1)}_6} by the Padé Method  

NASA Astrophysics Data System (ADS)

The q-Painlevé equation of type {E^{(1)}_6} is obtained by the Padé method. Special solutions in a determinant formula to the q-Painlevé equations are presented. A relation between the Padé method and Bäcklund transformations of type {E^{(1)}_6} is given.

Ikawa, Yusuke

2013-07-01

405

Electron impact collision strengths in Ne VII  

SciTech Connect

The lines of Ne VII have been observed in many astronomical objects, and some transitions from high energy levels were observed both in Seyfert galaxies and stellar coronae. Thus, the atomic data for these transitions are important for modeling. Using the code FAC we calculated the collision strengths based on the distorted-wave method with large configuration interactions included. The Maxwellian averaged effective collision strengths covering the typical temperature range of astronomical and laboratory hot plasmas are presented. We extend the calculation of the energy levels to n=4 and 5. The energy levels, wavelengths, spontaneous transition rates, weighted oscillator strengths, and effective collision strengths were reported. Compared with the results from experiment or previous theoretical calculations a general agreement is found. It is found that the resonance effects are important in calculating the effective collision strengths.

Di, L.; Shi, J.R.; Zhao, G., E-mail: gzhao@bao.ac.cn

2012-07-15

406

Development of K-Basin High-Strength Homogeneous Sludge Simulants and Correlations Between Unconfined Compressive Strength and Shear Strength  

SciTech Connect

K-Basin sludge will be stored in the Sludge Transport and Storage Containers (STSCs) at an interim storage location on Central Plateau before being treated and packaged for disposal. During the storage period, sludge in the STSCs may consolidate/agglomerate, potentially resulting in high-shear-strength material. The Sludge Treatment Project (STP) plans to use water jets to retrieve K-Basin sludge after the interim storage. STP has identified shear strength to be a key parameter that should be bounded to verify the operability and performance of sludge retrieval systems. Determining the range of sludge shear strength is important to gain high confidence that a water-jet retrieval system can mobilize stored K-Basin sludge from the STSCs. The shear strength measurements will provide a basis for bounding sludge properties for mobilization and erosion. Thus, it is also important to develop potential simulants to investigate these phenomena. Long-term sludge storage tests conducted by Pacific Northwest National Laboratory (PNNL) show that high-uranium-content K-Basin sludge can self-cement and form a strong sludge with a bulk shear strength of up to 65 kPa. Some of this sludge has 'paste' and 'chunks' with shear strengths of approximately 3-5 kPa and 380-770 kPa, respectively. High-uranium-content sludge samples subjected to hydrothermal testing (e.g., 185 C, 10 hours) have been observed to form agglomerates with a shear strength up to 170 kPa. These high values were estimated by measured unconfined compressive strength (UCS) obtained with a pocket penetrometer. Due to its ease of use, it is anticipated that a pocket penetrometer will be used to acquire additional shear strength data from archived K-Basin sludge samples stored at the PNNL Radiochemical Processing Laboratory (RPL) hot cells. It is uncertain whether the pocket penetrometer provides accurate shear strength measurements of the material. To assess the bounding material strength and potential for erosion, it is important to compare the measured shear strength to penetrometer measurements and to develop a correlation (or correlations) between UCS measured by a pocket penetrometer and direct shear strength measurements for various homogeneous and heterogeneous simulants. This study developed 11 homogeneous simulants, whose shear strengths vary from 4 to 170 kPa. With these simulants, we developed correlations between UCS measured by a Geotest E-280 pocket penetrometer and shear strength values measured by a Geonor H-60 hand-held vane tester and a more sophisticated bench-top unit, the Haake M5 rheometer. This was achieved with side-by-side measurements of the shear strength and UCS of the homogeneous simulants. The homogeneous simulants developed under this study consist of kaolin clay, plaster of Paris, and amorphous alumina CP-5 with water. The simulants also include modeling clay. The shear strength of most of these simulants is sensitive to various factors, including the simulant size, the intensity of mixing, and the curing time, even with given concentrations of simulant components. Table S.1 summarizes these 11 simulants and their shear strengths.

Onishi, Yasuo; Baer, Ellen BK; Chun, Jaehun; Yokuda, Satoru T.; Schmidt, Andrew J.; Sande, Susan; Buchmiller, William C.

2011-02-20

407

E1A Blocks Hyperphosphorylation of p130 and p107 without Affecting the Phosphorylation Status of the Retinoblastoma Protein  

PubMed Central

The phosphorylation status of the pRB family of growth suppressor proteins is regulated in a cell cycle entry-, progression-, and exit-dependent manner in normal cells. We have shown previously that p130, a member of this family, exhibits patterns of phosphorylated forms associated with various cell growth and differentiation stages. However, human 293 cells, which are transformed cells that express the adenoviral oncoproteins E1A and E1B, exhibit an abnormal pattern of p130 phosphorylated forms. Here we report that, unlike pRB, the phosphorylation status of both p130 and p107 is not modulated during the cell cycle in 293 cells as it is in other cells. Conditional overexpression of individual G1/S cyclins in 293 cells does not alter the phosphorylation status of p130, suggesting that the expression of E1A and/or E1B blocks hyperphosphorylation of p130. In agreement with these observations, transient cotransfection of vectors expressing E1A 12S, but not E1B, in combination with pocket proteins into U-2 OS cells blocks hyperphosphorylation of both p130 and p107. However, the phosphorylation status of pRB is not altered by cotransfection of E1A 12S vectors. Moreover, MC3T3-E1 preosteoblasts stably expressing E1A 12S also exhibit a block in hyperphosphorylation of endogenous p130 and p107. Direct binding of E1A to p130 and p107 is not required for the phosphorylation block since E1A 12S mutants defective in binding to the pRB family also block hyperphosphorylation of p130 and p107. Our data reported here identify a novel function of E1A, which affects p130 and p107 but does not affect pRB. Since E1A does not bind the hyperphosphorylated forms of p130, this function of E1A might prevent the existence of “free” hyperphosphorylated p130, which could act as a CDK inhibitor.

Parreno, Matilde; Garriga, Judit; Limon, Ana; Mayol, Xavier; Beck, George R.; Moran, Elizabeth; Grana, Xavier

2000-01-01

408

The relationship between tensile strength and flexure strength in fiber-reinforced composites  

Microsoft Academic Search

Tensile data on unidirectional composites generated from a flexure test usually yield a higher strength than observed from a standard tensile coupon. According to a statistical-strength theory based on a Weibull distribution, the presence of a stress gradient in the flexure-test results in an apparent increase in tensile strength as compared to the tensile test under uniform stress. In the

J. M. Whitney; M. Knight

1980-01-01

409

A case of PDH-E1 alpha mosaicism in a male patient with severe metabolic lactic acidosis.  

PubMed

We have characterized a novel mutation in a male patient that affects the coding sequence of PDH-E1 alpha gene and changes arginine-141 to a leucine. This nucleotide substitution was found in about 75% of the studied DNA (fibroblasts, liver and muscle), a scenario that would indicate a case of E1 alpha mosaicism in a male patient. When the mutant E1 alpha protein was expressed in human skin fibroblasts with zero endogenous pyruvate dehydrogenase complex activity and E1 alpha protein expression, no significant restoration of activity was recorded, in contrast to the wild-type cDNA. even though both wild-type and mutant protein levels were comparable. We concluded that the R141L mutation is a severe one and that it must have occurred in one of the E1 alpha alleles during early embryogenesis. PMID:11757583

Seyda, A; Chun, K; Packman, S; Robinson, B H

2001-10-01

410

E1a regions of the human adenoviruses and of the highly oncogenic simian adenovirus 7 are closely related.  

PubMed Central

Simian adenovirus 7 (SA7) is a highly oncogenic virus, capable of causing tumors in hamsters upon the direct injection of viral DNA. We determined the transcriptional organization of the transforming region and compared it with that of the human adenoviruses. This analysis demonstrated that there are two independently promoted transcription units similar to the E1a and E1b regions of the human adenoviruses. The nucleotide sequence of the SA7 E1a region demonstrated considerable homology with the human adenoviruses, both in the sequences that regulate E1a expression and in the encoded polypeptides. The amino acid homology was reflected in the ability of SA7 to complement the growth of human adenoviruses mutant in the E1a region. Furthermore, we found two regions of amino acid homology unique to SA7 and the highly oncogenic human adenovirus 12. Images

Kimelman, D; Miller, J S; Porter, D; Roberts, B E

1985-01-01

411

The E4 transcriptional unit of Ad2: far upstream sequences are required for its transactivation by E1A.  

PubMed Central

We have investigated the effect of the E1A polypeptides of adenovirus 2 on the transcription of the viral E4 region. For this purpose, we have fused the promoter region of the E4 gene to the bacterial gene coding for chloramphenicol acetyl transferase. We have found that transcription from the E4 promoter is increased at least 20 fold in the presence of the E1A region. We have also found that the largest E1A polypeptide is the regulating factor, whereas the shortest has no apparent effect. Deletion of sequences upstream from position -158, as measured from the cap site, reduces the efficiency of the transcription in the presence of E1A by more than 15 fold. An important regulatory domain lies between positions -158 and -179. This domain contains the sequence 5' GGGAAGTGAC 3' which is homologous to the E1A enhancer core sequence. Another similar sequence is also present at position -149. Images

Gilardi, P; Perricaudet, M

1984-01-01

412

Design, synthesis and molecular modeling of novel N-acylhydrazone derivatives as pyruvate dehydrogenase complex E1 inhibitors.  

PubMed

As potential inhibitors of pyruvate dehydrogenase complex E1 (PDHc-E1), a series of 19 1-((4-amino-2-methylpyrimidin-5-yl)methyl)-5-methyl-N'-(substituent)benzylidene-1H-1,2,3-triazole-4-carbohydrazide 4 has been synthesized and tested for their PDHc-E1 inhibitory activity in vitro. Some of these compounds such as 4a, 4g, 4l, 4o, 4p, and 4q were demonstrated to be effective inhibitors by the bioassay of Escherichia coli PDHc-E1. SAR analysis indicated that the PDHc-E1 inhibitory activity could be further enhanced by optimizing the substituted groups in the parent compound. Molecular modeling study with compound 4o as a model was performed to evaluate docking. The results of modeling study suggested a probable inhibition mechanism. PMID:24359707

He, Jun-Bo; Feng, Ling-Ling; Li, Jing; Tao, Rui-Juan; Ren, Yan-Liang; Wan, Jian; He, Hong-Wu

2014-01-01

413

Inhibition of Human Papillomavirus DNA Replication by an E1-Derived p80/UAF1-Binding Peptide  

PubMed Central

The papillomavirus E1 helicase is recruited by E2 to the viral origin, where it assembles into a double hexamer that orchestrates replication of the viral genome. We previously identified the cellular WD40 repeat-containing protein p80/UAF1 as a novel interaction partner of E1 from anogenital human papillomavirus (HPV) types. p80 was found to interact with the first 40 residues of HPV type 31 (HPV31) E1, and amino acid substitutions within this domain abrogated the maintenance of the viral episome in keratinocytes. In this study, we report that these p80-binding substitutions reduce by 70% the ability of E1 to support transient viral DNA replication without affecting its interaction with E2 and assembly at the origin in vivo. Microscopy studies revealed that p80 is relocalized from the cytoplasm to discrete subnuclear foci by E1 and E2. Chromatin immunoprecipitation assays further revealed that p80 is recruited to the viral origin in an E1- and E2-dependent manner. Interestingly, overexpression of a 40-amino-acid-long p80-binding peptide, derived from HPV31 E1, was found to inhibit viral DNA replication by preventing the recruitment of endogenous p80 to the origin. Mutant peptides defective for p80 interaction were not inhibitory, demonstrating the specificity of this effect. Characterization of this E1 peptide by nuclear magnetic resonance (NMR) showed that it is intrinsically disordered in solution, while mapping studies indicated that the WD repeats of p80 are required for E1 interaction. These results provide additional evidence for the requirement for p80 in anogenital HPV DNA replication and highlight the potential of E1-p80 interaction as a novel antiviral target.

Lehoux, Michael; Fradet-Turcotte, Amelie; Lussier-Price, Mathieu; Omichinski, James G.

2012-01-01

414

Mapping the Structure and Function of the E1 and E2 Glycoproteins in Alphaviruses  

PubMed Central

Summary The 9 Å resolution cryo-electron microscopy map of Sindbis virus presented here provides structural information on the polypeptide topology of the E2 protein, on the interactions between the E1 and E2 glycoproteins in the formation of a heterodimer, on the difference in conformation of the two types of trimeric spikes, on the interaction between the transmembrane helices of the E1 and E2 proteins, and on the conformational changes that occur when fusing with a host cell. The positions of various markers on the E2 protein established the approximate topology of the E2 structure. The largest conformational differences between the icosahedral surface spikes at icosahedral 3-fold and quasi-3-fold positions are associated with the monomers closest to the 5-fold axes. The long E2 monomers, containing the cell receptor recognition motif at their extremities, are shown to rotate by about 180° and to move away from the center of the spikes during fusion.

Mukhopadhyay, Suchetana; Zhang, Wei; Gabler, Stefan; Chipman, Paul R.; Strauss, Ellen G.; Strauss, James H.; Baker, Timothy S.; Kuhn, Richard J.; Rossmann, Michael G.

2009-01-01

415

Effect of E1 decay in the population of superdeformed structures  

NASA Astrophysics Data System (ADS)

Spectra of the yrast and excited superdeformed bands, forming the E2 quasi-continuum, are measured with the EUROBALL array for the nucleus 143Eu, in coincidence with high-energy ?-rays ( E?>3 MeV). It is found that the intensity population of the superdeformed states is enhanced by a factor of ?1.6 when a coincidence with a ?-ray with energy >6 MeV is required, in reasonable agreement with the increase of the line shape of the Giant Dipole Resonance built on a superdeformed configuration. This result shows that when an high energy E1 ?-ray is involved in the decay it is more likely connected with a SD rather than a ND nucleus. In addition, the analysis of the rotational quasi-continuum suggests the presence of a superdeformed component. The data are also compared and found consistent with simulation calculations of the relative intensities of the SD states, including the E1 decay of superdeformed nature.

Benzoni, G.; Bracco, A.; Camera, F.; Leoni, S.; Million, B.; Maj, A.; Algora, A.; Axelsson, A.; Bergström, M.; Blasi, N.; Castoldi, M.; Frattini, S.; Gadea, A.; Herskind, B.; Kmiecik, M.; Lo Bianco, G.; Nyberg, J.; Pignanelli, M.; Styczen, J.; Wieland, O.; Zieblinski, M.; Zucchiatti, A.

2002-08-01

416

A ColE1-encoded gene directs entry exclusion of the plasmid.  

PubMed Central

To detect entry exclusion of the ColE1 plasmid, we established an assay system that was not influenced by incompatibility of extant plasmids in the recipient cells or by the viability of the cells due to the killing action of colicin E1 protein. The assay revealed that exc1 and exc2, assigned as genes directing entry exclusion, had no exclusion activity. Instead, mbeD, which had been characterized as a gene for plasmid mobilization, directed the exclusion activity. MbeD was overexpressed and identified as a 35S-labeled protein, which was recovered in both the soluble and membrane fractions, particularly in the inner membrane fraction. An amphipathic helical structure was predicted in the N-terminal region of MbeD as well as in the corresponding homologous proteins of ColA and ColK. These proteins may bind to the inner membrane via the N-terminal amphipathic helix and function in entry exclusion.

Yamada, Y; Yamada, M; Nakazawa, A

1995-01-01

417

First Selenodetic Result from Chang'E-1 Lunar Orbiter Mission  

NASA Astrophysics Data System (ADS)

The first Chinese lunar orbiter, Chang'E-1, was sent to the circle polar orbit of the moon on Nov. 5. During the first month mission checkout period and the following normal mission period, it has been tracked using Range and RR and VLBI method. The tracking data may contribute to both of the OD and the POD of the mission. At the same time, the laser altimeter has been operated to measure the topography of the moon with very high accuracy and spatial resolution. Using the domestic tracking data, POD of Chang'E-1 mission was carried out. It is expected to merge the tracking data with other missions so as to improve the lunar global gravity field. By combining the POD data and attitude information as well as other necessary telemetry messages, the topography of the moon was renewed. Based on the renewed lunar DEM information and the lunar gravity field, the lunar crastial sphere and the Moho surface have been estimated using a downward continuation analyzing method. It may contribute to the selenodetic researches by combining with the historic data.

Ping, Jinsong; Huang, Qian; Yan, Jianguo; Shi, Xian; Wang, Guangli; Sha, Kai; Tang, Geshi; Chen, Ming; Cao, Jianfeng

418

Heterogeneity of adenovirus type 5 E1A proteins: multiple serine phosphorylations induce slow-migrating electrophoretic variants but do not affect E1A-induced transcriptional activation or transformation.  

PubMed Central

The 289-amino-acid product encoded by the adenovirus E1A 13S mRNA has several pleiotropic activities, including transcriptional activation, transcriptional repression, and when acting in concert with certain oncogene products, cell transformation. In all cell types in which E1A has been introduced (except bacteria), E1A protein is extensively posttranslationally modified to yield several isoelectric and molecular weight variants. The most striking variant is one that has a retarded mobility, by about Mr = 2,000, in sodium dodecyl sulfate gels. We have investigated the nature of this modification and have assessed its importance for E1A activity. Phosphorylation is responsible for the altered mobility of E1A, since acid phosphatase treatment eliminates the higher apparent molecular weight products. By using several E1A deletion mutants, we show that at least two seryl residues, residing between residues 86 and 120 and 224 and 289, are the sites of phosphorylation and that each phosphorylation can independently induce the mobility shift. However, E1A mutants lacking these seryl residues transcriptionally activate the adenovirus E3 and E2A promoters and transform baby rat kidney cells to near wild-type levels. Images

Richter, J D; Slavicek, J M; Schneider, J F; Jones, N C

1988-01-01

419

Cellular GCN5 Is a Novel Regulator of Human Adenovirus E1A-Conserved Region 3 Transactivation  

PubMed Central

The largest isoform of adenovirus early region 1A (E1A) contains a unique region termed conserved region 3 (CR3). This region activates viral gene expression by recruiting cellular transcription machinery to the early viral promoters. Recent studies have suggested that there is an optimal level of E1A-dependent transactivation required by human adenovirus (hAd) during infection and that this may be achieved via functional cross talk between the N termini of E1A and CR3. The N terminus of E1A binds GCN5, a cellular lysine acetyltransferase (KAT). We have identified a second independent interaction of E1A with GCN5 that is mediated by CR3, which requires residues 178 to 188 in hAd5 E1A. GCN5 was recruited to the viral genome during infection in an E1A-dependent manner, and this required both GCN5 interaction sites on E1A. Ectopic expression of GCN5 repressed transactivation by both E1A CR3 and full-length E1A. In contrast, RNA interference (RNAi) depletion of GCN5 or treatment with the KAT inhibitor cyclopentylidene-[4-(4?-chlorophenyl)thiazol-2-yl]hydrazone (CPTH2) resulted in increased E1A CR3 transactivation. Moreover, activation of the adenovirus E4 promoter by E1A was increased during infection of homozygous GCN5 KAT-defective (hat/hat) mouse embryonic fibroblasts (MEFs) compared to wild-type control MEFs. Enhanced histone H3 K9/K14 acetylation at the viral E4 promoter required the newly identified binding site for GCN5 within CR3 and correl