59 research outputs found
Combination treatment with highly bioavailable curcumin and NQO1 inhibitor exhibits potent antitumor effects on esophageal squamous cell carcinoma
Background: Esophageal squamous cell carcinoma (ESCC) is one of the most intractable cancers, so the development of novel therapeutics has been required to improve patient outcomes. Curcumin, a polyphenol from Curcuma longa, exhibits various health benefits including antitumor effects, but its clinical utility is limited because of low bioavailability. Theracurmin® (THC) is a highly bioavailable curcumin dispersed with colloidal submicron particles. Methods: We examined antitumor effects of THC on ESCC cells by cell viability assay, colony and spheroid formation assay, and xenograft models. To reveal its mechanisms, we investigated the levels of reactive oxygen species (ROS) and performed microarray gene expression analysis. According to those analyses, we focused on NQO1, which involved in the removal of ROS, and examined the effects of NQO1-knockdown or overexpression on THC treatment. Moreover, the therapeutic effect of THC and NQO1 inhibitor on ESCC patient-derived xenografts (PDX) was investigated. Results: THC caused cytotoxicity in ESCC cells, and suppressed the growth of xenografted tumors more efficiently than curcumin. THC increased ROS levels and activated the NRF2–NMRAL2P–NQO1 expressions. Inhibition of NQO1 in ESCC cells by shRNA or NQO1 inhibitor resulted in an increased sensitivity of cells to THC, whereas overexpression of NQO1 antagonized it. Notably, NQO1 inhibitor significantly enhanced the antitumor effects of THC in ESCC PDX tumors. Conclusions: These findings suggest the potential usefulness of THC and its combination with NQO1 inhibitor as a therapeutic option for ESCC
Spectral evolution of GRB 060904A observed with Swift and Suzaku -- Possibility of Inefficient Electron Acceleration
We observed an X-ray afterglow of GRB 060904A with the Swift and Suzaku
satellites. We found rapid spectral softening during both the prompt tail phase
and the decline phase of an X-ray flare in the BAT and XRT data. The observed
spectra were fit by power-law photon indices which rapidly changed from to within a few hundred
seconds in the prompt tail. This is one of the steepest X-ray spectra ever
observed, making it quite difficult to explain by simple electron acceleration
and synchrotron radiation. Then, we applied an alternative spectral fitting
using a broken power-law with exponential cutoff (BPEC) model. It is valid to
consider the situation that the cutoff energy is equivalent to the synchrotron
frequency of the maximum energy electrons in their energy distribution. Since
the spectral cutoff appears in the soft X-ray band, we conclude the electron
acceleration has been inefficient in the internal shocks of GRB 060904A. These
cutoff spectra suddenly disappeared at the transition time from the prompt tail
phase to the shallow decay one. After that, typical afterglow spectra with the
photon indices of 2.0 are continuously and preciously monitored by both XRT and
Suzaku/XIS up to 1 day since the burst trigger time. We could successfully
trace the temporal history of two characteristic break energies (peak energy
and cutoff energy) and they show the time dependence of while the following afterglow spectra are quite stable. This fact
indicates that the emitting material of prompt tail is due to completely
different dynamics from the shallow decay component. Therefore we conclude the
emission sites of two distinct phenomena obviously differ from each other.Comment: 19 pages, 9 figures, accepted for publication in PASJ (Suzaku 2nd
Special Issue
Electrical switching of vortex core in a magnetic disk
A magnetic vortex is a curling magnetic structure realized in a ferromagnetic
disk, which is a promising candidate of a memory cell for future nonvolatile
data storage devices. Thus, understanding of the stability and dynamical
behaviour of the magnetic vortex is a major requirement for developing magnetic
data storage technology. Since the experimental proof of the existence of a
nanometre-scale core with out-of-plane magnetisation in the magnetic vortex,
the dynamics of a vortex has been investigated intensively. However, the way to
electrically control the core magnetisation, which is a key for constructing a
vortex core memory, has been lacking. Here, we demonstrate the electrical
switching of the core magnetisation by utilizing the current-driven resonant
dynamics of the vortex; the core switching is triggered by a strong dynamic
field which is produced locally by a rotational core motion at a high speed of
several hundred m/s. Efficient switching of the vortex core without magnetic
field application is achieved thanks to resonance. This opens up the
potentiality of a simple magnetic disk as a building block for spintronic
devices like a memory cell where the bit data is stored as the direction of the
nanometre-scale core magnetisation.Comment: 20 pages, 4 figures. Supplementary discussion included. Accepted for
publication in Nature Material
Central object segmentation by deep learning for fruits and other roundish objects
We present CROP (Central Roundish Object Painter), which identifies and
paints the object at the center of an RGB image. Primarily CROP works for
roundish fruits in various illumination conditions, but surprisingly, it could
also deal with images of other organic or inorganic materials, or ones by
optical and electron microscopes, although CROP was trained solely by 172
images of fruits. The method involves image segmentation by deep learning, and
the architecture of the neural network is a deeper version of the original
U-Net. This technique could provide us with a means of automatically collecting
statistical data of fruit growth in farms. As an example, we describe our
experiment of processing 510 time series photos automatically to collect the
data on the size and the position of the target fruit. Our trained neural
network CROP and the above automatic programs are available on GitHub with
user-friendly interface programs.Comment: The version 2 contains a new section about the automatic processing
of time series photos. All the programs are available at
https://github.com/MotohisaFukuda/CRO
FTIR Detection of Protonation/Deprotonation of Key Carboxyl Side Chains Caused by Redox Change of the Cu A
Dependence of oxygen reduction reaction on temperature in (
Introduction Molten carbonate fuel cells (MCFCs) are in the beginning of commercialization due to their high energyconversion efficiency with a co-generation system. They have small activation loss due to their high operation temperature. In order to operate a MCFC at high pressure for the improvement of the energy conversion efficiency, there are some technological problems, mainly related to the durability of the materials. One of the most serious problems is the dissolution of NiO cathode. It causes Ni deposition and creates a short circuit. In order to prevent the Ni short circuit, La addition to the molten carbonate should be effective since it reduces the NiO solubility a lot. Furthermore, the oxygen solubility and the exchange current density of the oxygen reduction reaction (ORR) in the carbonate increase with La additive 2, 3 . However, temperature dependence of ORR has not been determined, and ORR has not been clarified enoug
An IL-27/Stat3 axis induces expression of programmed cell death 1 ligands (PD-L1/2) on infiltrating macrophages in lymphoma
Immune escape and tolerance in the tumor microenvironment are closely involved in tumor progression, and are caused by T-cell exhaustion and mediated by the inhibitory signaling of immune checkpoint molecules including programmed death-1 (PD-1), cytotoxic T-lymphocyte associated protein 4, and T-cell immunoglobulin and mucin domaincontaining molecule-3. In the present study, we investigated the expression of the PD-1 ligand 1 (PD-L1) in a lymphoma microenvironment using paraffin-embedded tissue samples, and subsequently studied the detailed mechanism of upregulation of PD-L1 on macrophages using cultured human macrophages and lymphoma cell lines. We found that macrophages in lymphoma tissues of almost all cases of adult T-cell leukemia/lymphoma (ATLL), follicular lymphoma and diffuse large B-cell lymphoma expressed PD-L1. Cell culture studies showed that the conditioned medium of ATL-T and SLVL cell lines induced increased expression of PD-L1/2 on macrophages, and that this PD-L1/2 overexpression was dependent on activation of signal transducer and activator of transcription 3 (Stat3). In vitro studies including cytokine array analysis showed that IL-27 (heterodimer of p28 and EBI3) induced overexpression of PD-L1/2 on macrophages via Stat3 activation. Because lymphoma cell lines produced IL-27B (EBI3) but not IL-27p28, it was proposed that the IL-27p28 derived from macrophages and the IL-27B (EBI3) derived from lymphoma cells formed an IL-27 (heterodimer) that induced PD-L1/2 overexpression. Although the significance of PD-L1/2 expressions on macrophages in lymphoma progression has never been clarified, an IL-27-Stat3 axis might be a target for immunotherapy for lymphoma patients
- …