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1.
Oncogene ; 42(22): 1832-1842, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37055552

RESUMO

Thrombospondin 1 (TSP1) is known for its cell-specific functions in cancer progression, such as proliferation and migration. It contains 22 exons that may potentially produce several different transcripts. Here, we identified TSP1V as a novel TSP1-splicing variant produced by intron retention (IR) in human thyroid cancer cells and tissues. We observed that TSP1V functionally inhibited tumorigenesis contrary to TSP1 wild-type, as identified in vivo and in vitro. These activities of TSP1V are caused by inhibiting phospho-Smad and phospho-focal adhesion kinase. Reverse transcription polymerase chain reaction and minigene experiments revealed that some phytochemicals/non-steroidal anti-inflammatory drugs enhanced IR. We further found that RNA-binding motif protein 5 (RBM5) suppressed IR induced by sulindac sulfide treatment. Additionally, sulindac sulfide reduced phospho-RBM5 levels in a time-dependent manner. Furthermore, trans-chalcone demethylated TSP1V, thereby preventing methyl-CpG-binding protein 2 binding to TSP1V gene. In addition, TSP1V levels were significantly lower in patients with differentiated thyroid carcinoma than in those with benign thyroid nodule, indicating its potential application as a diagnostic biomarker in tumor progression.


Assuntos
Trombospondina 1 , Glândula Tireoide , Humanos , Anti-Inflamatórios não Esteroides/farmacologia , Proteínas de Ciclo Celular/metabolismo , Transformação Celular Neoplásica/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a RNA , Trombospondina 1/genética , Trombospondina 1/metabolismo , Proteínas Supressoras de Tumor/metabolismo
2.
J Am Chem Soc ; 144(4): 1766-1777, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-35041412

RESUMO

At aqueous interfaces, the distribution and dynamics of adsorbates are modulated by the behavior of interfacial water. Hydration of a hydrophobic surface can store entropy via the ordering of interfacial water, which contributes to the Gibbs energy of solute binding. However, there is little experimental evidence for the existence of such entropic reservoirs, and virtually no precedent for their rational design in systems involving extended interfaces. In this study, two series of mesoporous silicas were modified in distinct ways: (1) progressively deeper thermal dehydroxylation, via condensation of surface silanols, and (2) increasing incorporation of nonpolar organic linkers into the silica framework. Both approaches result in decreasing average surface polarity, manifested in a blue-shift in the fluorescence of an adsorbed dye. For the inorganic silicas, hydrogen-bonding of water becomes less extensive as the number of surface silanols decreases. Overhauser dynamic nuclear polarization (ODNP) relaxometry indicates enhanced surface water diffusivity, reflecting a loss of enthalpic hydration. In contrast, organosilicas show a monotonic decrease in surface water diffusivity with decreasing polarity, reflecting enhanced hydrophobic hydration. Molecular dynamics simulations predict increased tetrahedrality of interfacial water for the organosilicas, implying increased ordering near the nm-size organic domains (relative to inorganic silicas, which necessarily lack such domains). These findings validate the prediction that hydrophobic hydration at interfaces is controlled by the microscopic length scale of the hydrophobic regions. They further suggest that the hydration thermodynamics of structurally heterogeneous silica surfaces can be tuned to promote adsorption, which in turn tunes the selectivity in catalytic reactions.

3.
Cancers (Basel) ; 13(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208730

RESUMO

Although the treatment of thyroid cancer has improved, unnecessary surgeries are performed due to a lack of specific diagnostic and prognostic markers. Therefore, the identification of novel biomarkers should be considered in the diagnosis and treatment of thyroid cancer. In this study, antibody arrays were performed using tumor and adjacent normal tissues of patients with papillary thyroid cancer, and several potential biomarkers were identified. Among the candidate proteins chosen based on the antibody array data, mature NAG-1 exhibited increased expression in tumor tissues compared to adjacent normal tissues. In contrast, pro-NAG-1 expression increased in normal tissues, as assessed by western blot analysis. Furthermore, pro-NAG-1 expression was increased when the thyroid cancer cells were treated with phytochemicals and nonsteroidal anti-inflammatory drugs in a dose-dependent manner. In particular, quercetin highly induced the expression of pro-NAG-1 but not that of mature NAG-1, with enhanced anticancer activity, including apoptosis induction and cell cycle arrest. Examination of the NAG-1 promoter activity showed that p53, C/EBPα, or C/EBPδ played a role in quercetin-induced NAG-1 expression. Overall, our study indicated that NAG-1 may serve as a novel biomarker for thyroid cancer prognosis and may be used as a therapeutic target for thyroid cancers.

4.
Chem Sci ; 11(14): 3702-3712, 2020 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33209241

RESUMO

Surface polarity plays a key role in controlling molecular adsorption at solid-liquid interfaces, with major implications for reactions and separations. In this study, the chemical composition of periodic mesoporous organosilicas (PMOs) was varied by co-condensing Si(OEt)4 with organodisilanes, to create a homologous series of materials with similar surface areas, pore volumes, and hydroxyl contents. Their relative surface polarities, obtained by measuring the fluorescence of a solvatochromic dye, cover a wide range. In this series of PMO materials, EPR spectra of tethered nitroxide radicals show monotonically decreasing mobility as larger fractions of the radicals interact strongly with increasingly non-polar surfaces. The surface properties of the materials also correlate with their affinities for organic molecules dissolved in various solvents. The most polar PMO has negligible affinity for phenol, p-cresol, or furfural when these molecules are dissolved in water. However, stronger solute-surface interactions and favor adsorption as the surface polarity decreases. The trend is reversed for furfural in benzene, where weaker solvent-surface interactions result in higher adsorption on polar surfaces. In DMSO, furfural adsorption is suppressed due to the similar strengths of solute-surface and solvent-surface interactions. Thus, the polarity of the surface relative to the solvent is critical for molecular adsorption. These findings show how adsorption/desorption can be precisely and systematically tuned by appropriate choice of both solvent and surface, and contribute to a predictive strategy for the design of catalytic and separations processes.

5.
Int J Mol Sci ; 21(12)2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32604902

RESUMO

Osteosarcoma is known to be one of the frequently occurring cancers in dogs. Its prognosis is usually very poor, with a high incidence of lung metastasis. Although radiation therapy has become a major therapeutic choice for canine osteosarcoma, the high costs and unexpected side effects prevent some patients from considering this treatment. Cold atmospheric plasma (CAP) is an ionized gas with high energy at low temperatures, and it produces reactive oxygen species that mediate many signaling pathways. Although many researchers have used CAP as an anticancer therapeutic approach in humans, its importance has been neglected in veterinary medicine. In this study, D-17 and DSN canine osteosarcoma cell lines were treated with CAP to observe its anticancer activity. By high-content screening and flow cytometry, CAP-treated cells showed growth arrest and apoptosis induction. Moreover, the osteosarcoma cells exhibited reduced migration and invasion activity when treated with CAP. Overall, CAP exerted an anticancer effect on canine osteosarcoma cell lines. CAP may have the potential to be used as a novel modality for treating cancer in veterinary medicine.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Ósseas/tratamento farmacológico , Osteossarcoma/tratamento farmacológico , Gases em Plasma/farmacologia , Animais , Apoptose , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Movimento Celular , Proliferação de Células , Cães , Osteossarcoma/metabolismo , Osteossarcoma/patologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas
6.
Sci Rep ; 7: 41981, 2017 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-28155913

RESUMO

Transparent and stretchable energy storage devices have attracted significant interest due to their potential to be applied to biocompatible and wearable electronics. Supercapacitors that use the reversible faradaic redox reaction of conducting polymer have a higher specific capacitance as compared with electrical double-layer capacitors. Typically, the conducting polymer electrode is fabricated through direct electropolymerization on the current collector. However, no research have been conducted on metal nanowires as current collectors for the direct electropolymerization, even though the metal nanowire network structure has proven to be superior as a transparent, flexible, and stretchable electrode platform because the conducting polymer's redox potential for polymerization is higher than that of widely studied metal nanowires such as silver and copper. In this study, we demonstrated a highly transparent and stretchable supercapacitor by developing Ag/Au/Polypyrrole core-shell nanowire networks as electrode by coating the surface of Ag NWs with a thin layer of gold, which provide higher redox potential than the electropolymerizable monomer. The Ag/Au/Polypyrrole core-shell nanowire networks demonstrated superior mechanical stability under various mechanical bending and stretching. In addition, proposed supercapacitors showed fine optical transmittance together with fivefold improved areal capacitance compared to pristine Ag/Au core-shell nanowire mesh-based supercapacitors.

7.
Nanoscale ; 9(5): 1978-1985, 2017 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-28105474

RESUMO

Although solution processed metal nanowire (NW) percolation networks are a strong candidate to replace commercial indium tin oxide, their performance is limited in thin film device applications due to reduced effective electrical areas arising from the dimple structure and percolative voids that single size metal NW percolation networks inevitably possess. Here, we present a transparent electrode based on a dual-scale silver nanowire (AgNW) percolation network embedded in a flexible substrate to demonstrate a significant enhancement in the effective electrical area by filling the large percolative voids present in a long/thick AgNW network with short/thin AgNWs. As a proof of concept, the performance enhancement of a flexible phosphorescent OLED is demonstrated with the dual-scale AgNW percolation network compared to the previous mono-scale AgNWs. Moreover, we report that mechanical and oxidative robustness, which are critical for flexible OLEDs, are greatly increased by embedding the dual-scale AgNW network in a resin layer.

8.
Nanotechnology ; 27(29): 295201, 2016 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-27276174

RESUMO

Since transparent conducting films based on silver nanowires (AgNWs) have shown higher transmittance and electrical conductivity compared to those of indium tin oxide (ITO) films, the electronics industry has recognized them as promising substitutes. However, due to the higher haze value of AgNW transparent conducting films compared to ITO films, the clarity is decreased when AgNW films are applied to optoelectronic devices. In this study, we develop a highly transparent, low-haze, very long AgNW percolation network. Moreover, we confirm that analyzed chemical roles can easily be applied to different AgNW synthesis methods, and that they have a direct impact on the nanowire shape. Consequently, the lengths of the wires are increased up to 200 µm and the diameters of the wires are decreased up to 45 nm. Using these results, we fabricate highly transparent (96%) conductors (100 Ω/sq) with low-haze (2%) without any annealing process. This electrode shows enhanced clarity compared to previous results due to the decreased diffusive transmittance and scattering. In addition, a flexible touchscreen using a AgNW network is demonstrated to show the performance of modified AgNWs.

9.
ACS Appl Mater Interfaces ; 8(24): 15449-58, 2016 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-27285849

RESUMO

Stretchable and transparent electronics have steadily attracted huge attention in wearable devices. Although Ag nanowire is the one of the most promising candidates for transparent and stretchable electronics, its electrochemical instability has forbidden its application to the development of electrochemical energy devices such as supercapacitors. Here, we introduce a highly stretchable and transparent supercapacitor based on electrochemically stable Ag-Au core-shell nanowire percolation network electrode. We developed a simple solution process to synthesize the Ag-Au core-shell nanowire with excellent electrical conductivity as well as greatly enhanced chemical and electrochemical stabilities compared to pristine Ag nanowire. The proposed core-shell nanowire-based supercapacitor still possesses fine optical transmittance and outstanding mechanical stability up to 60% strain. The Ag-Au core-shell nanowire can be a strong candidate for future wearable electrochemical energy devices.

10.
ACS Appl Mater Interfaces ; 8(18): 11575-82, 2016 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-27128365

RESUMO

Copper nanomaterials suffer from severe oxidation problem despite the huge cost effectiveness. The effect of two different processes for conventional tube furnace heating and selective laser sintering on copper nanoparticle paste is compared in the aspects of chemical, electrical and surface morphology. The thermal behavior of the copper thin films by furnace and laser is compared by SEM, XRD, FT-IR, and XPS analysis. The selective laser sintering process ensures low annealing temperature, fast processing speed with remarkable oxidation suppression even in air environment while conventional tube furnace heating experiences moderate oxidation even in Ar environment. Moreover, the laser-sintered copper nanoparticle thin film shows good electrical property and reduced oxidation than conventional thermal heating process. Consequently, the proposed selective laser sintering process can be compatible with plastic substrate for copper based flexible electronics applications.

11.
Mol Cells ; 29(5): 471-4, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20396966

RESUMO

Hypoxia-Inducible Factor-1 (HIF-1) plays an important role as a transcription factor under hypoxia. It activates numerous genes including those involved in angiogenesis, glucose metabolisms, cell proliferation and cell survival. The HIF-1 alpha subunit is regulated by 2-oxoglutarate (OG)- and Fe(II)-dependent hydroxylases, including Factor Inhibiting HIF-1 (FIH-1). FIH-1 hydroxylates Asn803 of HIF-1 alpha and blocks its interaction with co-activating molecules. Quinol family compounds such as 5-chloro-7-iodo-8-hydroxyquinoline (Clioquinol) have been shown to inhibit the hydroxylation activity of FIH-1. Here we determined the complex crystal structures of FIH-1: Clioquinol and FIH-1: 8-Hydroxyquinoline. Clioquinol and 8-Hydroxyquinoline bind to the active site of FIH-1 by coordinating the Fe(II) ion, thereby inhibiting the binding of a co-substrate, 2OG. Contrary to other known FIH-1 inhibitors that have negative charges, Clioquinol and 8-hydroxyquinoline are neutral in charge and can provide a template for improved inhibitor design that can selectively inhibit FIH-1.


Assuntos
Clioquinol/química , Inibidores Enzimáticos/química , Complexos Multiproteicos/química , Oxiquinolina/química , Proteínas Repressoras/química , Hipóxia Celular , Cristalização , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Ácidos Cetoglutáricos/metabolismo , Oxigenases de Função Mista , Complexos Multiproteicos/metabolismo , Ligação Proteica , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Proteínas Repressoras/metabolismo , Especificidade por Substrato
12.
Artigo em Inglês | MEDLINE | ID: mdl-19478455

RESUMO

Retinoic acid inducible gene-I (RIG-I) is an essential component of the innate immune system that is responsible for the detection and elimination of invading viruses. RIG-I recognizes viral RNAs inside the cell and then initiates downstream signalling to activate the IRF-3 and NF-kappaB genes, which results in the production of type I interferons. RIG-I is composed of an N-terminal CARD domain for signalling and C-terminal helicase and repressor domains for RNA recognition. A RIG-I-RNA binding assay was performed to investigate the in vitro RIG-I-RNA binding properties. Selenomethionine-incorporated RIG-I was expressed using Escherichia coli and purified for crystallization. X-ray data were collected from RIG-I-dsRNA complex crystals to 2.8 A resolution using synchrotron radiation.


Assuntos
Cristalografia por Raios X , RNA Helicases DEAD-box/metabolismo , RNA de Cadeia Dupla/metabolismo , Sequência de Aminoácidos , Clonagem Molecular , Cristalização , Proteína DEAD-box 58 , RNA Helicases DEAD-box/química , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/isolamento & purificação , Coleta de Dados , Escherichia coli/genética , Etídio/metabolismo , Corantes Fluorescentes/metabolismo , Histidina/química , Humanos , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Ligação Proteica , Estrutura Terciária de Proteína , Receptores Imunológicos , Estatística como Assunto , Síncrotrons , Temperatura
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