17 research outputs found

    An Improved Method for Obtaining Single-Phase Sr2MoO4 under Controlled Ultra-low Oxygen Partial Pressure

    Full text link
    We investigated a method for obtaining a sintered bulk sample of single-phase Sr2MoO4, which has recently increased in importance due to its similarities to superconducting Sr2RuO4. We discovered that with the aid of Ti2O3 as a p(O2) buffer, high-purity Sr2MoO4 is successfully synthesized in a sealed tube. We confirmed the space group and determined the exact elemental composition of the compound in order to establish its stoichiometry. The guideline for the rational choice of a p(O2)-buffer material is discussed.Comment: 4 pages, 4 figure

    Soft-templated synthesis of mesoporous nickel oxide using poly(styrene-block-acrylic acid-block-ethylene glycol) block copolymers

    Get PDF
    In this work, we report the soft-templated preparation of mesoporous nickel oxide using an asymmetric poly(styrene-block-acrylic acid-block-ethylene glycol) (PS-b-PAA-b-PEG) triblock copolymer. This block copolymer forms a micelle consisting of a PS core, a PAA shell and a PEG corona in aqueous solutions, which can serve as a soft template. Specifically, the PS block forms the core of the micelles on the basis of its lower solubility in water. The anionic PAA block interacts with the cationic Ni ions present in the solution to generate the shell. The PEG block forms the corona of the micelles and stabilizes the micelles by preventing secondary aggregation through steric repulsion between the PEG chains. In terms of textural characteristics, the as-synthesized mesoporous NiO exhibits a large average pore size of 35 nm with large specific surface area and pore volume of 97.0 m g and 0.411 cm g, respectively. It is expected that the proposed soft-templated strategy can be expanded to other metal oxides/sulfides in the future for potential applications in gas sensors, catalysis, energy storage and conversion, optoelectronics, and biomedical applications

    Radiosensitization of human lung cancer cells by the novel purine-scaffold Hsp90 inhibitor, PU-H71.

    No full text
    The molecular chaperone heat shock protein 90 (Hsp90) is involved in the maturation and stabilization of a wide range of oncogenic client proteins for oncogenesis and malignant cell proliferation, which renders this protein a promising target in the development of cancer therapeutics. PU-H71 is a purine-scaffold Hsp90 inhibitor with less toxicity in normal cells than in cancer cells. In this study, we examined the in vitro radiosensitizing activity and molecular mechanisms of action of PU-H71 in human lung cancer cell lines. PU-H71 enhanced the sensitivity of the SQ-5 and A549 cancer cells to radiation. When the cancer cells were pre-treated with PU-H71, the repair of DNA double-strand breaks (DSBs) was markedly inhibited after irradiation compared with the cells that were not pre-treated with PU-H71, as evaluated by counting the foci of phosphorylated histone H2AX (γ-H2AX). We further demonstrated that post-irradiation, PU-H71 inhibited Rad51 foci formation, a critical protein for the homologous recombination pathway of DNA DSB repair. These data indicate that targeting Hsp90 with PU-H71 may be novel therapeutic strategy for radioresistant carcinomas

    Proteomic identification and validation of novel interactions of the putative tumor suppressor PRELP with membrane proteins including IGFI-R and p75NTR

    No full text
    Proline and arginine-rich end leucine-rich repeat protein (PRELP) is a member of the small leucine-rich repeat proteoglycans (SLRPs) family. Levels of PRELP mRNA are downregulated in many types of cancer, and PRELP has been reported to have suppressive effects on tumor cell growth, although the molecular mechanism has yet to be fully elucidated. Given that other SLRPs regulate signaling pathways through interactions with various membrane proteins, we reasoned that PRELP likely interacts with membrane proteins to maintain cellular homeostasis. To identify membrane proteins that interact with PRELP, we carried out coimmunoprecipitation coupled with mass spectrometry (CoIP-MS). We prepared membrane fractions from Expi293 cells transfected to overexpress FLAG-tagged PRELP or control cells and analyzed samples precipitated with anti-FLAG antibody by mass spectrometry. Comparison of membrane proteins in each sample identified several that seem to interact with PRELP; among them, we noted two growth factor receptors, insulin-like growth factor I receptor (IGFI-R) and low-affinity nerve growth factor receptor (p75NTR), interactions with which might help to explain PRELP’s links to cancer. We demonstrated that PRELP directly binds to extracellular domains of these two growth factor receptors with low micromolar affinities by surface plasmon resonance analysis using recombinant proteins. Furthermore, cell-based analysis using recombinant PRELP protein showed that PRELP suppressed cell growth and affected cell morphology of A549 lung carcinoma cells, also at micromolar concentration. These results suggest that PRELP regulates cellular functions through interactions with IGFI-R and p75NTR and provide a broader set of candidate partners for further exploration

    Surface-polarity-dependent Raman spectra of ultrathin silicon carbide crystal

    No full text
    The surface-polarity-dependent Raman spectra of ultrathin silicon carbide crystal are reported. The relative Raman intensity of the folded-transverse-acoustic phonon to the folded-transverse-optical phonon modes differs drastically between silicon-terminated face (Si-face) and carbon-terminated face (C-face) only for sample thickness below 150 nm. For samples thicker than 150 nm, the relative Raman intensity ratio takes an almost constant value for both Si- and C-faces. These results indicate that the phonon modes confined in the near-surface region are the possible origin of the observed surface-polarity-dependent Raman spectra

    Accessory corpora lutea formation in pregnant Hokkaido sika deer (Cervus nippon yesoensis) investigated by examination of ovarian dynamics and steroid hormone concentrations

    Get PDF
    Generally, sika deer conceive a single fetus, but approximately 80% of pregnant females have two corpora lutea (CLs). The function of the accessory CL (ACL) is unknown; moreover, the process of ACL formation is unclear, and understanding this is necessary to know its role. To elucidate the process of ACL formation, the ovarian dynamics of six adult Hokkaido sika deer females were examined ultrasonographically together with peripheral estradiol-17 beta and progesterone concentrations. ACLs formed in three females that conceived at the first estrus of the breeding season, but not in those females that conceived at the second estrus. After copulation, postconception ovulation of the dominant follicle of the first wave is induced by an increase in estradiol-17 beta, which leads to formation of an ACL. A relatively low concentration of progesterone after the first estrus of the breeding season is considered to be responsible for the increase in estradiol-17 beta after copulation

    Immunochemoradiotherapy for Patients with Oral Squamous Cell Carcinoma: Augmentation of OK-432-Induced Helper T Cell 1 Response by 5-FU and X-ray Irradiation

    Get PDF
    Eighty-one patients with oral squamous cell carcinoma (OSCC) received oral fluoropyrimidine UFT and radiotherapy (RT) with or without an immunotherapeutic agent OK-432. Both overall survival and progression-free survival of patients who received RT + UFT + OK-432 were significantly longer than those of patients who received RT + UFT (P = .0075 and P = .0175, respectively). Clinical response was also more favorable in RT + UFT + OK-432 group than in RT + UFT group (P = .0066). Next, in vitro experiments were conducted to examine the effect of 5-fluorouracil (5-FU) and X-ray irradiation in OK-432-induced immunity. Human peripheral blood mononuclear cells stimulated with OK-432 produced helper T cell 1 (Th1)-type cytokines as well as interleukin-10 (IL-10) and transforming growth factor-β (TGF-β), which are produced by Th2 and regulatory T cells (Tregs), respectively, and are inhibitory in antitumor immunity. OK-432-induced IL-10 and TGF-β but not Th1 cytokines were significantly inhibited by 5-FU and/or X-ray. 5-FU and X-ray also inhibited the expression of mRNAs for GATA-3 and Foxp3, which are transcription factors for Th2 and Tregs, respectively, but not for T-bet, a transcription factor for Th1. In addition, 5-FU and X-ray decreased the expression of mRNAs for suppressor of cytokine signaling 1 (SOCS1) and SOCS3. Antisense oligonucleotides for SOCS1 and SOCS3 markedly reduced OK-432-induced IL-10 and TGF-β. This is the first report clearly demonstrating that OK-432-based immunotherapy significantly enhanced the therapeutic effects of chemoradiotherapy in patients with OSCC as well as elucidating the mechanism of the synergistic effect of immunochemoradiotherapy in which 5-FU and radiation enhanced OK-432-induced Th1 response mediated by the inhibition of SOCS1 and SOCS3 gene expression
    corecore