3,288 research outputs found

    Intelligent Gold Nanoparticles with Oncogenic MicroRNA-Dependent Activities to Manipulate Tumorigenic Environments for Synergistic Tumor Therapy

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    Tumorigenic environments, especially aberrantly overexpressed oncogenic microRNAs, play a critical role in various activities of tumor progression. However, developing strategies to effectively utilize and manipulate these oncogenic microRNAs for tumor therapy is still a challenge. To address this challenge, spherical nucleic acids (SNAs) consisting of gold nanoparticles in the core and antisense oligonucleotides as the shell are fabricated. Hybridized to the oligonucleotide shell is a DNA sequence to which doxorubicin is conjugated (DNA-DOX). The oligonucleotides shell is designed to capture overexpressed miR-21/miR-155 and inhibit the expression of these oncogenic miRNAs in tumor cells after tumor accumulation to manipulate genetic environment for accurate gene therapy. This process further induces the aggregation of these SNAs, which not only generates photothermal agents to achieve on-demand photothermal therapy in situ, but also enlarges the size of SNAs to enhance the retention time in the tumor for sustained therapy. The capture of the relevant miRNAs simultaneously triggers the intracellular release of the DNA-DOX from the SNAs to deliver tumor-specific chemotherapy. Both in vivo and in vitro results indicate that this combination strategy has excellent tumor inhibition properties with high survival rate of tumor-bearing mice, and can thus be a promising candidate for effective tumor treatment

    Measurement of \psip Radiative Decays

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    Using 14 million psi(2S) events accumulated at the BESII detector, we report first measurements of branching fractions or upper limits for psi(2S) decays into gamma ppbar, gamma 2(pi^+pi^-), gamma K_s K^-pi^++c.c., gamma K^+ K^- pi^+pi^-, gamma K^{*0} K^- pi^+ +c.c., gamma K^{*0}\bar K^{*0}, gamma pi^+pi^- p pbar, gamma 2(K^+K^-), gamma 3(pi^+pi^-), and gamma 2(pi^+pi^-)K^+K^- with the invariant mass of hadrons below 2.9GeV/c^2. We also report branching fractions of psi(2S) decays into 2(pi^+pi^-) pi^0, omega pi^+pi^-, omega f_2(1270), b_1^\pm pi^\mp, and pi^0 2(pi^+pi^-) K^+K^-.Comment: 5 pages, 4 figure

    Observation of Y(2175) in J/ψ→ηϕf0(980)J/\psi\to \eta\phi f_0(980)

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    The decays of J/ψ→ηϕf0(980)(η→γγ,ϕ→K+K−,f0(980)→π+π−)J/\psi\to \eta\phi f_0(980) (\eta\to \gamma\gamma, \phi \to K^+K^-, f_0(980)\to\pi^+\pi^-) are analyzed using a sample of 5.8×1075.8 \times 10^{7} J/ψJ/\psi events collected with the BESII detector at the Beijing Electron-Positron Collider (BEPC). A structure at around 2.182.18 GeV/c2c^2 with about 5σ5\sigma significance is observed in the ϕf0(980)\phi f_0(980) invariant mass spectrum. A fit with a Breit-Wigner function gives the peak mass and width of m=2.186±0.010(stat)±0.006(syst)m=2.186\pm 0.010 (stat)\pm 0.006 (syst) GeV/c2c^2 and Γ=0.065±0.023(stat)±0.017(syst)\Gamma=0.065\pm 0.023 (stat)\pm 0.017 (syst) GeV/c2c^2, respectively, that are consistent with those of Y(2175), observed by the BABAR collaboration in the initial-state radiation (ISR) process e+e−→γISRϕf0(980)e^+e^-\to\gamma_{ISR}\phi f_0(980). The production branching ratio is determined to be Br(J/ψ→ηY(2175))⋅Br(Y(2175)→ϕf0(980))⋅Br(f0(980)→π+π−)=(3.23±0.75(stat)±0.73(syst))×10−4Br(J/\psi\to\eta Y(2175))\cdot Br(Y(2175)\to\phi f_0(980))\cdot Br(f_0(980)\to\pi^+\pi^-)=(3.23\pm 0.75 (stat)\pm0.73 (syst))\times 10^{-4}, assuming that the Y(2175) is a 1−−1^{--} state.Comment: 5 pages, 4 figures, accepted by Phys. Rev. Let

    Measurements of J/ψJ/\psi and ψ(2S)\psi(2S) decays into ΛΛˉπ0\Lambda \bar{\Lambda}\pi^0 and ΛΛˉη\Lambda \bar{\Lambda}\eta

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    Using 58 million J/ψJ/\psi and 14 million ψ(2S)\psi(2S) events collected by the BESII detector at the BEPC, branching fractions or upper limits for the decays J/ψJ/\psi and ψ(2S)→ΛΛˉπ0\psi(2S) \to \Lambda \bar{\Lambda}\pi^0 and ΛΛˉη\Lambda \bar{\Lambda}\eta are measured. For the isospin violating decays, the upper limits are determined to be B(J/ψ→ΛΛˉπ0)<6.4×10−5{\cal B}(J/\psi \to \Lambda \bar{\Lambda}\pi^0)<6.4\times 10^{-5} and B(ψ(2S)→ΛΛˉπ0)<4.9×10−5{\cal B}(\psi(2S) \to \Lambda \bar{\Lambda}\pi^0)<4.9\times 10^{-5} at the 90% confidence level. The isospin conserving process J/ψ→ΛΛˉηJ/\psi \to \Lambda \bar{\Lambda}\eta is observed for the first time, and its branching fraction is measured to be B(J/ψ→ΛΛˉη)=(2.62±0.60±0.44)×10−4{\cal B}(J/\psi \to \Lambda \bar{\Lambda}\eta)=(2.62\pm 0.60\pm 0.44)\times 10^{-4}, where the first error is statistical and the second one is systematic. No ΛΛˉη\Lambda \bar{\Lambda}\eta signal is observed in ψ(2S)\psi(2S) decays, and B(ψ(2S)→ΛΛˉη)<1.2×10−4{\cal B}(\psi(2S) \to \Lambda \bar{\Lambda}\eta)<1.2\times 10^{-4} is set at the 90% confidence level. Branching fractions of J/ψJ/\psi decays into Σ+π−barΛ\Sigma^+ \pi^- bar{\Lambda} and Σˉ−π+Λ\bar{\Sigma}^- \pi^+ \Lambda are also reported, and the sum of these branching fractions is determined to be B(J/ψ→Σ+π−Λˉ+c.c.)=(1.52±0.08±0.16)×10−3{\cal B}(J/\psi \to \Sigma^+\pi^- \bar{\Lambda} + c.c.)=(1.52\pm 0.08\pm 0.16)\times 10^{-3}.Comment: 7 pages, 10 figures. Phys.Rev.D comments considere

    Tough, self-healable and tissue-adhesive hydrogel with tunable multifunctionality

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    This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.An ideal hydrogel for biomedical engineering should mimic the intrinsic properties of natural tissue, especially high toughness and self-healing ability, in order to withstand cyclic loading and repair skin and muscle damage. In addition, excellent cell affinity and tissue adhesiveness enable integration with the surrounding tissue after implantation. Inspired by the natural mussel adhesive mechanism, we designed a polydopamine–polyacrylamide (PDA–PAM) single network hydrogel by preventing the overoxidation of dopamine to maintain enough free catechol groups in the hydrogel. Therefore, the hydrogel possesses super stretchability, high toughness, stimuli-free self-healing ability, cell affinity and tissue adhesiveness. More remarkably, the current hydrogel can repeatedly be adhered on/stripped from a variety of surfaces for many cycles without loss of adhesion strength. Furthermore, the hydrogel can serve as an excellent platform to host various nano-building blocks, in which multiple functionalities are integrated to achieve versatile potential applications, such as magnetic and electrical therapies

    Measurements of J/\psi decays into \omega K \bar{K} \pi and \phi K \bar{K} \pi

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    The decays of J/ψ→ωKKˉπJ/\psi \to \omega K\bar{K}\pi and J/ψ→ϕKKˉπJ/\psi \to \phi K\bar{K}\pi are studied using 5.8×1075.8 \times 10^{7} J/ψJ/\psi events collected with the Beijing Spectrometer (BESII) at the Beijing Electron-Positron Collider (BEPC). The KS0K±π∓K^{0}_{S}K^{\pm}\pi^{\mp} and K+K−π0K^{+}K^{-}\pi^{0} systems, produced in J/ψ→ωKKˉπJ/\psi \to \omega K\bar{K}\pi, have enhancements in the invariant mass distributions at around 1.44 GeV/c2c^{2}. However, there is no evidence for mass enhancements in the KKˉπK\bar{K}\pi system in J/ψ→ϕKKˉπJ/\psi \to \phi K\bar{K}\pi. The branching fractions of J/ψ→ωKS0K±π∓J/\psi \to \omega K^{0}_{S}K^{\pm}\pi^{\mp}, ϕKS0K±π∓\phi K^{0}_{S}K^{\pm}\pi^{\mp}, ωK∗Kˉ+c.c.\omega K^{*}\bar{K}+c.c., and ϕK∗Kˉ+c.c.\phi K^{*}\bar{K}+c.c. are obtained, and the J/ψ→ηKS0K±π∓J/\psi \to \eta K^{0}_{S}K^{\pm}\pi^{\mp} branching fraction is measured for the first time.Comment: 18 pages, 10 figure
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