239 research outputs found

    Aspisol inhibits tumor growth and induces apoptosis in breast cancer

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    Nonsteroidal anti-inflammatory drugs inhibit cell proliferation and induce apoptosis in various cancer cell lines, which is considered to be an important mechanism for their anti-tumor activity and cancer prevention. However, the molecular mechanisms through which these compounds induce apoptosis are not well understood. Aim: to determine the effects of nonselective cyclooxygenase-2 (COX-2) inhibitor, aspisol on breast cancer cells in vitro and in vivo. Methods: The cytotoxic activity of aspisol was evaluated by MTT assay. The apoptosis index of cells was measured by flow cytometry. Immunohistochemical staining was used to detect expressions of COX-2 and caspase-3 in MDA-MB-231 cells. The expression of bcl-2 and bax was analyzed by Western blot analysis. The content of prostaglandin E2 (PGE2) in MDA-MB-231 cells was estimated by ELISA. In vivo apoptosis of the tumor cells was detected by the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL). Results: Our results showed that aspisol reduced viability of MDA-MB-231 cells in time- and dose- dependent fashions and induced apoptosis by increase of caspase-3 and bax expressions while decrease of COX-2 and bcl-2 expression in vitro. In addition, exposure to aspisol decreased the basal release of PGE2. In vivo, aspisol also inhibited the proliferation of breast cancer cells and induced their apoptosis. Conclusions: Our in vitro and in vivo data indicated that the antitumor effects of aspisol on breast cancer cells was probably mediated by the induction of apoptosis, and it could be linked to the downregulation of the COX-2 or bcl-2 expression and up-regulation of caspase-3 or bax expression.НСстСроидныС ΠΏΡ€ΠΎΡ‚ΠΈΠ²ΠΎΠ²ΠΎΡΠΏΠ°Π»ΠΈΡ‚Π΅Π»ΡŒΠ½Ρ‹Π΅ ΠΏΡ€Π΅ΠΏΠ°Ρ€Π°Ρ‚Ρ‹ ΠΈΠ½Π³ΠΈΠ±ΠΈΡ€ΡƒΡŽΡ‚ ΠΏΡ€ΠΎΠ»ΠΈΡ„Π΅Ρ€Π°Ρ†ΠΈΡŽ ΠΊΠ»Π΅Ρ‚ΠΎΠΊ ΠΈ Π²Ρ‹Π·Ρ‹Π²Π°ΡŽΡ‚ Π°ΠΏΠΎΠΏΡ‚ΠΎΠ· Π²ΠΎ ΠΌΠ½ΠΎΠ³ΠΈΡ… ΠΎΠΏΡƒΡ…ΠΎΠ»Π΅Π²Ρ‹Ρ… ΠΊΠ»Π΅Ρ‚ΠΎΡ‡Π½Ρ‹Ρ… линиях, Ρ‡Ρ‚ΠΎ считаСтся Π²Π°ΠΆΠ½Ρ‹ΠΌ ΠΌΠ΅Ρ…Π°Π½ΠΈΠ·ΠΌΠΎΠΌ ΠΈΡ… ΠΏΡ€ΠΎΡ‚ΠΈΠ²ΠΎΠΎΠΏΡƒΡ…ΠΎΠ»Π΅Π²ΠΎΠΉ активности ΠΈ ΠΏΡ€ΠΎΡ„ΠΈΠ»Π°ΠΊΡ‚ΠΈΠΊΠΈ развития Ρ€Π°ΠΊΠ°. Π’Π΅ΠΌ Π½Π΅ ΠΌΠ΅Π½Π΅Π΅ молСкулярныС ΠΌΠ΅Ρ…Π°Π½ΠΈΠ·ΠΌΡ‹ апоптотичСского дСйствия этих ΠΏΡ€Π΅ΠΏΠ°Ρ€Π°Ρ‚ΠΎΠ² ΠΈΠ·ΡƒΡ‡Π΅Π½Ρ‹ нСдостаточно. ЦСль: ΠΈΠ·ΡƒΡ‡ΠΈΡ‚ΡŒ дСйствиС нСспСцифичСского ΠΈΠ½Π³ΠΈΠ±ΠΈΡ‚ΠΎΡ€Π° циклогСксиназы-2 (COX-2) β€” аспизола β€” Π½Π° злокачСствСнныС ΠΊΠ»Π΅Ρ‚ΠΊΠΈ Ρ€Π°ΠΊΠ° ΠΌΠΎΠ»ΠΎΡ‡Π½ΠΎΠΉ ΠΆΠ΅Π»Π΅Π·Ρ‹ in vitro ΠΈ in vivo. ΠœΠ΅Ρ‚ΠΎΠ΄Ρ‹: Π²Ρ‹ΠΆΠΈΠ²Π°Π΅ΠΌΠΎΡ‚ΡŒ ΠΊΠ»Π΅Ρ‚ΠΎΠΊ MDA-MB-231 опрСдСляли с ΠΏΠΎΠΌΠΎΡ‰ΡŒΡŽ MTT-тСста. АпоптотичСский индСкс измСряли с ΠΏΠΎΠΌΠΎΡ‰ΡŒΡŽ ΠΏΡ€ΠΎΡ‚ΠΎΡ‡Π½ΠΎΠΉ Ρ†ΠΈΡ‚ΠΎΠΌΠ΅Ρ‚Ρ€ΠΈΠΈ ΠΈ иммуногистохимичСским ΠΎΠΊΡ€Π°ΡˆΠΈΠ²Π°Π½ΠΈΠ΅ΠΌ с Π°Π½Ρ‚ΠΈΡ‚Π΅Π»Π°ΠΌΠΈ ΠΏΡ€ΠΎΡ‚ΠΈΠ² COX-2 ΠΈ каспазы-3. Π­ΠΊΡΠΏΡ€Π΅ΡΡΠΈΡŽ bcl-2 ΠΈ bax ΠΈΠ·ΡƒΡ‡Π°Π»ΠΈ с ΠΏΠΎΠΌΠΎΡ‰ΡŒΡŽ ВСстСрн-Π±Π»ΠΎΡ‚-Π°Π½Π°Π»ΠΈΠ·Π°. Π‘ΠΎΠ΄Π΅Ρ€ΠΆΠ°Π½ΠΈΠ΅ простагландина E2 (PGE2 ) Π² ΠΊΠ»Π΅Ρ‚ΠΊΠ°Ρ… MDA-MB-231 ΠΎΡ†Π΅Π½ΠΈΠ²Π°Π»ΠΈ ΠΌΠ΅Ρ‚ΠΎΠ΄ΠΎΠΌ ELISA. In vivo Π°ΠΏΠΎΠΏΡ‚ΠΎΠ· ΠΎΠΏΡƒΡ…ΠΎΠ»Π΅Π²Ρ‹Ρ… ΠΊΠ»Π΅Ρ‚ΠΎΠΊ опрСдСляли ΠΏΡƒΡ‚Π΅ΠΌ выявлСния Ρ€Π°Π·Ρ€Ρ‹Π²ΠΎΠ² Π”ΠΠš с ΠΏΠΎΠΌΠΎΡ‰ΡŒΡŽ ΠΊΠΎΠ½Ρ†Π΅Π²ΠΎΠΉ дСзоксинуклСот-ΠΈΠ΄ΠΈΠ»Ρ‚Ρ€Π°Π½Ρ„Π΅Ρ€Π°Π·Ρ‹ (ΠΌΠ΅Ρ‚ΠΎΠ΄ TUNEL). Π Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚Ρ‹: ΠΏΠΎΠΊΠ°Π·Π°Π½ΠΎ, Ρ‡Ρ‚ΠΎ Π² зависимости ΠΎΡ‚ Π²Ρ€Π΅ΠΌΠ΅Π½ΠΈ ΠΈΠ½ΠΊΡƒΠ±Π°Ρ†ΠΈΠΈ ΠΈ Π΄ΠΎΠ·Ρ‹ аспизол ΡƒΠ³Π½Π΅Ρ‚Π°Π» рост ΠΊΠ»Π΅Ρ‚ΠΎΠΊ MDA-MB-231 in vitro ΠΈ Π²Ρ‹Π·Ρ‹Π²Π°Π» ΠΈΡ… Π°ΠΏΠΎΠΏΡ‚ΠΎΠ· Π½Π° Ρ„ΠΎΠ½Π΅ ΠΏΠΎΠ²Ρ‹ΡˆΠ΅Π½ΠΈΡ экспрСссии каспазы-3 ΠΈ bax, Π° Ρ‚Π°ΠΊΠΆΠ΅ сниТСния экспрСссии COX-2 ΠΈ bcl-2. Π’ условиях in vivo аспизол Ρ‚Π°ΠΊΠΆΠ΅ ΠΈΠ½Π³ΠΈΠ±ΠΈΡ€ΠΎΠ²Π°Π» ΠΏΡ€ΠΎΠ»ΠΈΡ„Π΅Ρ€Π°Ρ†ΠΈΡŽ злокачСствСнных ΠΊΠ»Π΅Ρ‚ΠΎΠΊ Ρ€Π°ΠΊΠ° ΠΌΠΎΠ»ΠΎΡ‡Π½ΠΎΠΉ ΠΆΠ΅Π»Π΅Π·Ρ‹ ΠΈ Π²Ρ‹Π·Ρ‹Π²Π°Π» ΠΈΡ… Π°ΠΏΠΎΠΏΡ‚ΠΎΠ·. Π’Ρ‹Π²ΠΎΠ΄Ρ‹: Π΄Π°Π½Π½Ρ‹Π΅, ΠΏΠΎΠ»ΡƒΡ‡Π΅Π½Π½Ρ‹Π΅ in vitro ΠΈ in vivo, ΡΠ²ΠΈΠ΄Π΅Ρ‚Π΅Π»ΡŒΡΡ‚Π²ΡƒΡŽΡ‚ ΠΎ ΠΏΡ€ΠΎΡ‚ΠΈΠ²ΠΎΠΎΠΏΡƒΡ…ΠΎΠ»Π΅Π²ΠΎΠΌ эффСктС аспизола Π½Π° ΠΊΠ»Π΅Ρ‚ΠΊΠΈ Ρ€Π°ΠΊΠ° ΠΌΠΎΠ»ΠΎΡ‡Π½ΠΎΠΉ ΠΆΠ΅Π»Π΅Π·Ρ‹, Ρ‡Ρ‚ΠΎ скорСС всСго опосрСдовано Π΅Π³ΠΎ проапоптотичСским дСйствиСм ΠΈ ΠΌΠΎΠΆΠ΅Ρ‚ Π±Ρ‹Ρ‚ΡŒ связано со сниТСниСм экспрСссии COX-2 ΠΈ bcl-2, Π° Ρ‚Π°ΠΊΠΆΠ΅ ΠΏΠΎΠ²Ρ‹ΡˆΠ΅Π½ΠΈΠ΅ΠΌ экспрСссии каспазы-3 ΠΈ bax

    Critical Currents of Ideal Quantum Hall Superfluids

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    Filling factor Ξ½=1\nu=1 bilayer electron systems in the quantum Hall regime have an excitonic-condensate superfluid ground state when the layer separation dd is less than a critical value dcd_c. On a quantum Hall plateau current injected and removed through one of the two layers drives a dissipationless edge current that carries parallel currents, and a dissipationless bulk supercurrent that carries opposing currents in the two layers. In this paper we discuss the theory of finite supercurrent bilayer states, both in the presence and in the absence of symmetry breaking inter-layer hybridization. Solutions to the microscopic mean-field equations exist at all condensate phase winding rates for zero and sufficiently weak hybridization strengths. We find, however, that collective instabilities occur when the supercurrent exceeds a critical value determined primarily by a competition between direct and exchange inter-layer Coulomb interactions. The critical current is estimated using a local stability criterion and varies as (dcβˆ’d)1/2(d_c-d)^{1/2} when dd approaches dcd_c from below. For large inter-layer hybridization, we find that the critical current is limited by a soliton instability of microscopic origin.Comment: 18 RevTeX pgs, 21 eps figure

    Long-distant contribution and Ο‡c1\chi_{c1} radiative decays to light vector meson

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    The discrepancy between the PQCD calculation and the CLEO data for Ο‡c1β†’Ξ³V\chi_{c1}\to \gamma V (V=ρ0, ω, ϕV=\rho^0,\,\omega,\,\phi) stimulates our interest in exploring extra mechanism of Ο‡c1\chi_{c1} decay. In this work, we apply an important non-perturbative QCD effect, i.e., hadronic loop mechanism, to study Ο‡c1β†’Ξ³V\chi_{c1}\to \gamma V radiative decay. Our numerical result shows that the theoretical results including the hadronic loop contribution and the PQCD calculation of Ο‡c1β†’Ξ³V\chi_{c1}\to \gamma V are consistent with the corresponding CLEO data of Ο‡c1β†’Ξ³V\chi_{c1}\to \gamma V. We expect further experimental measurement of Ο‡c1β†’Ξ³V\chi_{c1}\to \gamma V at BES-III, which will be helpful to test the hadronic loop effect on Ο‡c1\chi_{c1} decay.Comment: 7 pages, 2 figures. Accepted for publication in Eur. Phys. J.

    Topological Superfluid in one-dimensional Ultracold Atomic System with Spin-Orbit Coupling

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    We propose a one-dimensional Hamiltonian H1DH_{1D} which supports Majorana fermions when dx2βˆ’y2d_{x^{2}-y^{2}}-wave superfluid appears in the ultracold atomic system and obtain the phase-separation diagrams both for the time-reversal-invariant case and time-reversal-symmetry-breaking case. From the phase-separation diagrams, we find that the single Majorana fermions exist in the topological superfluid region, and we can reach this region by tuning the chemical potential ΞΌ\mu and spin-orbit coupling Ξ±R\alpha_{R}. Importantly, the spin-orbit coupling has realized in ultracold atoms by the recent experimental achievement of synthetic gauge field, therefore, our one-dimensional ultra-cold atomic system described by H1DH_{1D} is a promising platform to find the mysterious Majorana fermions.Comment: 5 papers, 2 figure

    QED3 theory of underdoped high temperature superconductors

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    Low-energy theory of d-wave quasiparticles coupled to fluctuating vortex loops that describes the loss of phase coherence in a two dimensional d-wave superconductor at T=0 is derived. The theory has the form of 2+1 dimensional quantum electrodynamics (QED3), and is proposed as an effective description of the T=0 superconductor-insulator transition in underdoped cuprates. The coupling constant ("charge") in this theory is proportional to the dual order parameter of the XY model, which is assumed to be describing the quantum fluctuations of the phase of the superconducting order parameter. The principal result is that the destruction of phase coherence in d-wave superconductors typically, and immediately, leads to antiferromagnetism. The transition can be understood in terms of the spontaneous breaking of an approximate "chiral" SU(2) symmetry, which may be discerned at low enough energies in the standard d-wave superconductor. The mechanism of the symmetry breaking is analogous to the dynamical mass generation in the QED3, with the "mass" here being proportional to staggered magnetization. Other insulating phases that break chiral symmetry include the translationally invariant "d+ip" and "d+is" insulators, and various one dimensional charge-density and spin-density waves. The theory offers an explanation for the rounded d-wave-like dispersion seen in ARPES experiments on Ca2CuO2Cl2 (F. Ronning et. al., Science 282, 2067 (1998)).Comment: Revtex, 20 pages, 5 figures; this is a much extended follow-up to the Phys. Rev. Lett. vol.88, 047006 (2002) (cond-mat/0110188); improved presentation, many additional explanations, comments, and references added, sec. IV rewritten. Final version, to appear in Phys. Rev.

    Charmless Bs→PP,PV,VVB_s\to PP, PV, VV Decays Based on the six-quark Effective Hamiltonian with Strong Phase Effects II

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    We provide a systematic study of charmless Bs→PP,PV,VVB_s \to PP, PV, VV decays (PP and VV denote pseudoscalar and vector mesons, respectively) based on an approximate six-quark operator effective Hamiltonian from QCD. The calculation of the relevant hard-scattering kernels is carried out, the resulting transition form factors are consistent with the results of QCD sum rule calculations. By taking into account important classes of power corrections involving "chirally-enhanced" terms and the vertex corrections as well as weak annihilation contributions with non-trivial strong phase, we present predictions for the branching ratios and CP asymmetries of BsB_s decays into PP, PV and VV final states, and also for the corresponding polarization observables in VV final states. It is found that the weak annihilation contributions with non-trivial strong phase have remarkable effects on the observables in the color-suppressed and penguin-dominated decay modes. In addition, we discuss the SU(3) flavor symmetry and show that the symmetry relations are generally respected

    Geometric phase in the Kitaev honeycomb model and scaling behavior at critical points

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    In this paper a geometric phase of the Kitaev honeycomb model is derived and proposed to characterize the topological quantum phase transition. The simultaneous rotation of two spins is crucial to generate the geometric phase for the multi-spin in a unit-cell unlike the one-spin case. It is found that the ground-state geometric phase, which is non-analytic at the critical points, possesses zigzagging behavior in the gapless BB phase of non-Abelian anyon excitations, but is a smooth function in the gapped AA phase. Furthermore, the finite-size scaling behavior of the non-analytic geometric phase along with its first- and second-order partial derivatives in the vicinity of critical points is shown to exhibit the universality. The divergent second-order derivative of geometric phase in the thermodynamic limit indicates the typical second-order phase transition and thus the topological quantum phase transition can be well described in terms of the geometric-phase.Comment: 7 pages, 8 figure

    Phenomenological Analysis of B->PP Decays with QCD Factorization

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    In this paper, we study nonleptonic charmless B decays to two light pseudoscalar mesons within the frame of QCD factorization, including the contributions from the chirally enhanced power corrections and weak annihilation. Predictions for the CP-averaged branching ratios and CP-violating asymmetries are given. Within the reasonable range of the parameters, we find that our predictions for the branching ratios of B -> PP are consistent with the present experimental data. But because of the logarithmic divergences at the endpoints in the hard spectator scatterings and weak annihilation, there are still large uncertainties in these predictions.Comment: 34 pages, 5 figures. to appear in PR

    X(3872) and Other Possible Heavy Molecular States

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    We perform a systematic study of the possible molecular states composed of a pair of heavy mesons such as DDΛ‰D\bar D, Dβˆ—DΛ‰D^\ast\bar D, Dβˆ—DΛ‰βˆ—D^\ast \bar D^\ast in the framework of the meson exchange model. The exchanged mesons include the pseudoscalar, scalar and vector mesons. Through our investigation, we find that (1) the structure X(3764) is not a molecular state; (2) There exists strong attraction in the range r<1r < 1 fm for the Dβˆ—DΛ‰βˆ—D^*\bar D^* system with J=0,1J=0, 1. If future experiments confirm Z+(4051)Z^+(4051) as a loosely bound molecular state, its quantum number is probably JP=0+J^{P}=0^+. Its partner state Ξ¦βˆ—βˆ—0\Phi^{**0} may be searched for in the Ο€0Ο‡c1\pi^0\chi_{c1} channel; (3) The vector meson exchange provides strong attraction in the Dβˆ—DΛ‰D^\ast \bar D channel together with the pion exchange. A bound state solution exists with a reasonable cutoff parameter Ξ›βˆΌ1.4\Lambda\sim 1.4 GeV. X(3872) may be accommodated as a molecular state dynamically although drawing a very definite conclusion needs further investigation; (4) The Bβˆ—BΛ‰B^\ast \bar B molecular state exists.Comment: 21 pages, 17 tables, 11 figures. Typos correcte

    Analysis of the X(1835) and related baryonium states with Bethe-Salpeter equation

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    In this article, we study the mass spectrum of the baryon-antibaryon bound states ppΛ‰p\bar{p}, ΣΣˉ\Sigma\bar{\Sigma}, ΞžΞžΛ‰\Xi\bar{\Xi}, ΛΛˉ\Lambda\bar{\Lambda}, pNΛ‰(1440)p\bar{N}(1440), ΣΣˉ(1660)\Sigma\bar{\Sigma}(1660), ΞžΞžΛ‰β€²\Xi\bar{\Xi}^\prime and ΛΛˉ(1600)\Lambda\bar{\Lambda}(1600) with the Bethe-Salpeter equation. The numerical results indicate that the ppΛ‰p\bar{p}, ΣΣˉ\Sigma\bar{\Sigma}, ΞžΞžΛ‰\Xi\bar{\Xi}, pNΛ‰(1440)p\bar{N}(1440), ΣΣˉ(1660)\Sigma\bar{\Sigma}(1660), ΞžΞžΛ‰β€²\Xi\bar{\Xi}^\prime bound states maybe exist, and the new resonances X(1835) and X(2370) can be tentatively identified as the ppΛ‰p\bar{p} and pNΛ‰(1440)p\bar{N}(1440) (or N(1400)pΛ‰N(1400)\bar{p}) bound states respectively with some gluon constituents, and the new resonance X(2120) may be a pseudoscalar glueball. On the other hand, the Regge trajectory favors identifying the X(1835), X(2120) and X(2370) as the excited Ξ·β€²(958)\eta^\prime(958) mesons with the radial quantum numbers n=3n=3, 4 and 5, respectively.Comment: 13 pages, 2 figures, revise a numbe
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