5,096 research outputs found
(-)-Epigallocatechin-3-Gallate Induces Non-Apoptotic Cell Death in Human Cancer Cells via ROS-Mediated Lysosomal Membrane Permeabilization
10.1371/journal.pone.0046749PLoS ONE710
Generation of Intense High-Order Vortex Harmonics
This paper presents the method for the first time to generate intense
high-order optical vortices that carry orbital angular momentum in the extreme
ultraviolet region. In three-dimensional particle-in-cell simulation, both the
reflected and transmitted light beams include high-order harmonics of the
Laguerre-Gaussian (LG) mode when a linearly polarized LG laser pulse impinges
on a solid foil. The mode of the generated LG harmonic scales with its order,
in good agreement with our theoretical analysis. The intensity of the generated
high-order vortex harmonics is close to the relativistic region, and the pulse
duration can be in attosecond scale. The obtained intense vortex beam possesses
the combined properties of fine transversal structure due to the high-order
mode and the fine longitudinal structure due to the short wavelength of the
high-order harmonics. Thus, the obtained intense vortex beam may have
extraordinarily promising applications for high-capacity quantum information
and for high-resolution detection in both spatial and temporal scales because
of the addition of a new degree of freedom
Multifunctional dendrimer/combretastatin A4 inclusion complexes enable in vitro targeted cancer therapy
Mengen Zhang1,2, Rui Guo2, Yin Wang2, Xueyan Cao2, Mingwu Shen2, Xiangyang Shi1-31State Key Laboratory for Modification of Chemical Fibers and Polymer Materials; 2College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai, People’s Republic of China; 3Centro de Química da Madeira, Universidade da Madeira, Campus da Penteada, Funchal, PortugalBackground: We report here a unique approach to using multifunctional dendrimer/combretastatin A4 (CA4) inclusion complexes for targeted cancer therapeutics.Methods: Amine-terminated generation 5 polyamidoamine dendrimers were first partially acetylated to neutralize a significant portion of the terminal amines, and then the remaining dendrimer terminal amines were sequentially modified with fluorescein isothiocyanate as an imaging agent and folic acid as a targeting ligand. The multifunctional dendrimers formed (G5.NHAc-FI-FA) were utilized to encapsulate the anticancer drug, CA4, for targeted delivery into cancer cells overexpressing folic acid receptors.Results: The inclusion complexes of G5.NHAc-FI-FA/CA4 formed were stable and are able to significantly improve the water solubility of CA4 from 11.8 to 240 µg/mL. In vitro release studies showed that the multifunctional dendrimers complexed with CA4 could be released in a sustained manner. Both 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide colorimetric assay and morphological cell observation showed that the inhibitory effect of the G5.NHAc-FI-FA/CA4 complexes was similar to that of free CA4 at the same selected drug concentration. More importantly, the complexes were able to target selectively and display specific therapeutic efficacy to cancer cells overexpressing high-affinity folic acid receptors.Conclusion: Multifunctional dendrimers may serve as a valuable carrier to form stable inclusion complexes with various hydrophobic anticancer drugs with improved water solubility, for targeting chemotherapy to different types of cancer.Keywords: PAMAM dendrimers, combretastatin A4, inclusion complexes, targeted cancer therap
Functionalized halloysite nanotube-based carrier for intracellular delivery of antisense oligonucleotides
Halloysites are cheap, abundantly available, and natural with high mechanical strength and biocompatibility. In this paper, a novel halloysite nanotube [HNT]-based gene delivery system was explored for loading and intracellular delivery of antisense oligodeoxynucleotides [ASODNs], in which functionalized HNTs [f-HNTs] were used as carriers and ASODNs as a therapeutic gene for targeting survivin. HNTs were firstly surface-modified with γ-aminopropyltriethoxysilane in order to facilitate further biofunctionalization. The f-HNTs and the assembled f-HNT-ASODN complexes were characterized by transmission electron microscopy [TEM], dynamic light scattering, UV-visible spectroscopy, and fluorescence spectrophotometry. The intracellular uptake and delivery efficiency of the complexes were effectively investigated by TEM, confocal microscopy, and flow cytometry. In vitro cytotoxicity studies of the complexes using MTT assay exhibited a significant enhancement in the cytotoxic capability. The results exhibited that f-HNT complexes could efficiently improve intracellular delivery and enhance antitumor activity of ASODNs by the nanotube carrier and could be used as novel promising vectors for gene therapy applications, which is attributed to their advantages over structures and features including a unique tubular structure, large aspect ratio, natural availability, rich functionality, good biocompatibility, and high mechanical strength
Measuring the X-ray luminosities of DESI groups from eROSITA Final Equatorial-Depth Survey: I. X-ray luminosity - halo mass scaling relation
We use the eROSITA Final Equatorial-Depth Survey (eFEDS) to measure the
rest-frame 0.1-2.4 keV band X-ray luminosities of 600,000 DESI groups
using two different algorithms in the overlap region of the two observations.
These groups span a large redshift range of and group
mass range of .
(1) Using the blind detection pipeline of eFEDS, we find that 10932 X-ray
emission peaks can be cross matched with our groups, of which have
signal-to-noise ratio in X-ray detection. Comparing to
the numbers reported in previous studies, this matched sample size is a factor
of larger. (2) By stacking X-ray maps around groups with similar
masses and redshifts, we measure the average X-ray luminosity of groups as a
function of halo mass in five redshift bins. We find, in a wide halo mass
range, the X-ray luminosity, , is roughly linearly proportional to
, and is quite independent to the redshift of the groups. (3) We use a
Poisson distribution to model the X-ray luminosities obtained using two
different algorithms and obtain best-fit and scaling relations, respectively. The best-fit
slopes are flatter than the results previously obtained, but closer to a
self-similar prediction.Comment: 15 pages, 13 figures, accepted for publication in MNRA
Generation of Ultra-intense Gamma-ray Train by QED Harmonics
When laser intensity exceeds 10^22W/cm^2, photons with energy above MeV can
be generated from high-order harmonics process in the laser-plasma interaction.
We find that under such laser intensity, QED effect plays a dominating role in
the radiation pattern. Contrast to the gas and relativistic HHG processes, both
the occurrence and energy of gamma-ray emission produced by QED harmonics are
random and QED harmonics are usually not coherent, while the property of high
intensity and ultra-short duration is conserved. Our simulation shows that the
period of gamma-ray train is half of the laser period and the peak intensity is
1.4e22W/cm^2. This new harmonic production with QED effects are crucial to
light-matter interaction in strong field and can be verified in experiments by
10PW laser facilities in the near future.Comment: 12 pages, 4 figure
Proton Acceleration in Underdense Plasma by Ultraintense Laguerre-Gaussian Laser Pulse
Three-dimensional particle-in-cell simulation is used to investigate the
witness proton acceleration in underdense plasma with a short intense
Laguerre-Gaussian (LG) laser pulse. Driven by the LG10 laser pulse, a special
bubble with an electron pillar on the axis is formed, in which protons can be
well-confined by the generated transversal focusing field and accelerated by
the longitudinal wakefield. The risk of scattering prior to acceleration with a
Gaussian laser pulse in underdense plasma is avoided, and protons are
accelerated stably to much higher energy. In simulation, a proton beam has been
accelerated to 7 GeV from 1 GeV in underdense tritium plasma driven by a
2.14x1022 W/cm2 LG10 laser pulse
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