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1.
Adv Mater ; 35(24): e2210511, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36930970

RESUMEN

Further optimization of perovskite light-emitting diodes (PeLEDs) is impeded by crystal deformation caused by residual stress and defect formation with subsequent non-radiative recombination. Molecular additives for defect passivation are widely studied; however, the majority have insulating properties that hinder charge injection and transport. Herein, highly efficient green-emitting PeLEDs are reported by introducing semiconducting molecular additives (Fl-OEGA and Fl-C8A). Transmission electron microscopy shows that conjugated additives exist primarily at the grain boundaries of perovskite, and Kelvin probe force microscopy confirms that the variation in contact potential difference between grain boundaries and perovskite crystal domains is significantly reduced. The residual tensile stress is reduced by 13% and the activation energy for ion migration increases in the Fl-OEGA-treated perovskite film, compared to those of the film without additives. Compared to insulating 2,2'-(ethylenedioxy)diethylamine (EDEA), the introduction of semiconducting additives prevents a significant reduction in the charge-transport capability. Furthermore, the PeLEDs with Fl-OEGA show a negligible shift in the turn-on voltage and a significantly smaller decrease in the current density with increasing Fl-OEGA compared to the devices with EDEA. Finally, the 3D CsPbBr3 -PeLEDs show the highest external quantum efficiency of 21.3% by the incorporation of semiconducting Fl-OEGA as a new multifunctional additive.

2.
Brief Bioinform ; 25(1)2023 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-38180829

RESUMEN

Forecasting the interaction between compounds and proteins is crucial for discovering new drugs. However, previous sequence-based studies have not utilized three-dimensional (3D) information on compounds and proteins, such as atom coordinates and distance matrices, to predict binding affinity. Furthermore, numerous widely adopted computational techniques have relied on sequences of amino acid characters for protein representations. This approach may constrain the model's ability to capture meaningful biochemical features, impeding a more comprehensive understanding of the underlying proteins. Here, we propose a two-step deep learning strategy named MulinforCPI that incorporates transfer learning techniques with multi-level resolution features to overcome these limitations. Our approach leverages 3D information from both proteins and compounds and acquires a profound understanding of the atomic-level features of proteins. Besides, our research highlights the divide between first-principle and data-driven methods, offering new research prospects for compound-protein interaction tasks. We applied the proposed method to six datasets: Davis, Metz, KIBA, CASF-2016, DUD-E and BindingDB, to evaluate the effectiveness of our approach.


Asunto(s)
Aminoácidos , Mapeo de Interacción de Proteínas , Conformación Proteica , Unión Proteica
3.
ACS Nano ; 16(4): 5795-5806, 2022 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-35311268

RESUMEN

One-dimensional hybrid nanostructures composed of a plasmonic gold nanowire core covered by a shell of magnetic oxide nanoparticles (Au@FexOy NWs) were synthesized by a one-pot solvothermal synthesis process. The effects of reaction temperature, time, reducing agent, and precursor as well as postsynthesis treatment were optimized to produce highly uniform NWs with a diameter of 226 ± 25 nm and a plasmonic core aspect ratio of 25 to 82. By exploiting the interaction of NWs with an external magnetic field, precise arrangements into highly periodic photonic structures were achieved, which can generate distinctive structural colors that are vividly iridescent and polarization-sensitive. Furthermore, a Bouligand-type chiral nematic film consisting of multistacked unidirectional layers of achiral NWs was fabricated using a modified layer-by-layer deposition method, which displays circular dichroism (CD) and chiral sensing capability. The addition of bovine serum albumin (BSA) as a model protein analyte induced a concentration-dependent wavelength shift of CD peaks. These intriguing properties of magnetoplasmonic anisotropic NWs and their self-assemblies could be consequently valuable for developing nature-inspired structural color imprints as well as solid-state chiral sensing devices.


Asunto(s)
Nanopartículas , Nanoestructuras , Nanocables , Nanocables/química , Oro/química , Nanoestructuras/química , Nanopartículas/química , Dicroismo Circular
4.
Bioinformatics ; 37(Suppl_1): i376-i382, 2021 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-34252937

RESUMEN

MOTIVATION: Identifying mechanism of actions (MoA) of novel compounds is crucial in drug discovery. Careful understanding of MoA can avoid potential side effects of drug candidates. Efforts have been made to identify MoA using the transcriptomic signatures induced by compounds. However, these approaches fail to reveal MoAs in the absence of actual compound signatures. RESULTS: We present MoAble, which predicts MoAs without requiring compound signatures. We train a deep learning-based coembedding model to map compound signatures and compound structure into the same embedding space. The model generates low-dimensional compound signature representation from the compound structures. To predict MoAs, pathway enrichment analysis is performed based on the connectivity between embedding vectors of compounds and those of genetic perturbation. Results show that MoAble is comparable to the methods that use actual compound signatures. We demonstrate that MoAble can be used to reveal MoAs of novel compounds without measuring compound signatures with the same prediction accuracy as that with measuring them. AVAILABILITY AND IMPLEMENTATION: MoAble is available at https://github.com/dmis-lab/moable. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Programas Informáticos , Transcriptoma , Descubrimiento de Drogas
5.
Cells ; 9(3)2020 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-32164386

RESUMEN

Atopic dermatitis (AD) is a multifactorial, heterogeneous disease associated with epidermal barrier disruption and intense systemic inflammation. Previously, we showed that exosomes derived from human adipose tissue-derived mesenchymal stem cells (ASC-exosomes) attenuate AD-like symptoms by reducing multiple inflammatory cytokine levels. Here, we investigated ASC-exosomes' effects on skin barrier restoration by analyzing protein and lipid contents. We found that subcutaneous injection of ASC-exosomes in an oxazolone-induced dermatitis model remarkably reduced trans-epidermal water loss, while enhancing stratum corneum (SC) hydration and markedly decreasing the levels of inflammatory cytokines such as IL-4, IL-5, IL-13, TNF-α, IFN-γ, IL-17, and TSLP, all in a dose-dependent manner. Interestingly, ASC-exosomes induced the production of ceramides and dihydroceramides. Electron microscopic analysis revealed enhanced epidermal lamellar bodies and formation of lamellar layer at the interface of the SC and stratum granulosum with ASC-exosomes treatment. Deep RNA sequencing analysis of skin lesions demonstrated that ASC-exosomes restores the expression of genes involved in skin barrier, lipid metabolism, cell cycle, and inflammatory response in the diseased area. Collectively, our results suggest that ASC-exosomes effectively restore epidermal barrier functions in AD by facilitating the de novo synthesis of ceramides, resulting in a promising cell-free therapeutic option for treating AD.


Asunto(s)
Tejido Adiposo/metabolismo , Ceramidas/biosíntesis , Dermatitis Atópica/tratamiento farmacológico , Epidermis/metabolismo , Exosomas/metabolismo , Células Madre Mesenquimatosas/metabolismo , Animales , Ceramidas/metabolismo , Dermatitis Atópica/patología , Femenino , Humanos , Ratones
6.
J Nanosci Nanotechnol ; 20(7): 4358-4363, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31968474

RESUMEN

We report the relation between the catalyst patterning conditions and the intensity of the 1st order Raman active modes in Au-catalyzed GaAs nanowire bundles. We fabricated e-beam lithographically Au-patterned GaAs(111)B substrates by varying the patterning conditions (e-beam dose rate, dot-size and interdot-spacings), and grew GaAs nanowires via vapor-liquid-solid process using a solid-source molecular beam epitaxy. To understand the effects of the substrate preparation conditions and resulting morphologies on the optical characteristics of 1st order transverse optical and longitudinal optical phonon modes of GaAs, we characterized the nanowire bundles using complementary µ-Raman spectroscopy and scanning electron microscopy as a function of the e-beam dose rate (145-595 µC/cm²), inter-dot spacing (100 and 150 nm) and pattern size (100 and 150 nm). Ensembles of single crystalline GaAs nanowires covered with different Au-thickness exhibit a downshift and asymmetric broadening of the 1st order transverse optical and longitudinal optical phonon peaks relative to GaAs bulk modes. We also showed that the sensitivity of a downshift and broadening of Raman spectra are directly related to morphological and surface coverage variations in as-grown nanowires. We observed clear increases of the transverse optical and longitudinal optical intensity as well as the relatively higher peak shift and broadening of Raman spectra from the 100 nm patterning in response to the dose rate change. Strong dependence of Raman spectra of the nanowire bundles on the e-beam dose rate changes are attributed to the variations in spatial density, size, shape and random growth orientation of the wires. We have shown that the identification of the changes in GaAs longitudinal optical and Arsenic anti-site peaks is good indicators to characterize the quality of as-grown GaAs nanowires. Our finding confirms the utilization of Raman spectroscopy as a powerful tool for characterizing chemical, structural, and morphological information of as-grown nanowires within the supporting substrate.

7.
J Nanosci Nanotechnol ; 20(7): 4444-4449, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31968493

RESUMEN

We report the systematic investigation of the surface optical phonon modes in Au-catalyzed GaAs nanowires grown on an Au pre-patterned GaAs(111)B substrate using µ-Raman spectroscopy. We employed electron-beam dose rate as a control parameter during the substrate patterning step for adjusting the nanowire base diameter and coverage, which are independent from the nanowire growth conditions. We have experimentally studied the effect of the fill factor and average diameter on the surface optical phonon modes and explained the red-shift and broadening of the surface optical phonon frequencies by employing the dielectric continuum model. The surface optical phonon mode shift is exhibited to be sensitive to fill factor, rather than base diameter. The decrease in the average diameter from 280 nm to 180 nm results in the asymmetric broadening and red-shift of the surface optical phonon frequency (~1.83 cm-1) but the theoretical calculation from the isolated single nanowire-based dielectric continuum model cannot solely explain the behaviors of the surface optical phonon mode. In contrast, the change in the fill factor from 0.01 to 0.83 results in a shift of the surface optical phonon frequency (~6.5 cm-1) from the GaAs bulk value. The red-shift and asymmetric broadening of the surface optical phonons, in an agreement with the Maxwell-Garnett approximation, are consequences of dipolar interaction of randomly aligned neighboring nanowires and the polar nature of GaAs nanowire bundles. This work suggests the pre-patterning parameter dependent surface optical phonon characteristics of GaAs nanowire bundles which are of great importance in the nondestructive characterization of low-dimensional opto-electronic materials and devices.

8.
Iran J Public Health ; 47(Suppl 1): 9-18, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30186807

RESUMEN

BACKGROUND: This study aimed to investigate the trend of physical activity and daily sports participation in the Korean aged population through the review of 'Research on Public Daily Sports Participation' published by the Ministry of Culture, Sports and Tourism. The main purpose was to suggest the best health and sports policy for the future. METHODS: The result of the research conducted by the government was published 13 times in total from 1989 to 2015. The aged were defined as people in their 60s and 70s since 2006. Based on the research published 7 times from 2006 to 2015, this study analyzed the changes and the trend recognition of health status, physical activities, sports activity effects and environment in the aged population in South Korea. RESULTS: Majority of the aged population was found to hardly recognize their health status, but positively aware of physical and sports activity effect, particularly that the sports facility environment has been improving. Therefore, it is encouraged to set up elderly-friendly routine sports environment to motivate their participation and consequently establish healthy exercise culture. CONCLUSION: This study has great significance as it suggests the direction of future health and sports policy by analyzing the trend of previous physical activities and daily sports participation among the aged population based on the government-published research.

10.
Diabetes Metab J ; 41(5): 393-404, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29086538

RESUMEN

BACKGROUND: This is part of a prospective study carried out as a national project to secure standardized public resources for type 2 diabetes mellitus (T2DM) patients in Korea. We compared various characteristics of long-standing T2DM patients with diabetic retinopathy (DR) and macular edema (ME). METHODS: From September 2014 to July 2015, T2DM patients with disease duration of at least 15 years were recruited at a single university hospital. Clinical data and samples were collected according to the common data elements and standards of procedure developed by the Korean Diabetes Association Research Council. Each participant was assessed by ophthalmologists for DR and ME. RESULTS: Among 220 registered patients, 183 completed the ophthalmologic assessment. DR was associated with longer disease duration (odds ratio [OR], 1.071; 95% confidence interval [CI], 1.001 to 1.147 for non-proliferative diabetic retinopathy [NPDR]) (OR, 1.142; 95% CI, 1.051 to 1.242 for proliferative diabetic retinopathy [PDR]) and the use of long-acting insulin (OR, 4.559; 95% CI, 1.672 to 12.427 for NPDR) (OR, 4.783; 95% CI, 1.581 to 14.474 for PDR), but a lower prevalence of a family history of cancer (OR, 0.310; 95% CI, 0.119 to 0.809 for NPDR) (OR, 0.206; 95% CI, 0.063 to 0.673 for PDR). ME was associated with higher glycosylated hemoglobin levels (OR, 1.380; 95% CI, 1.032 to 1.845) and the use of rapid-acting insulin (OR, 5.211; 95% CI, 1.445 to 18.794). CONCLUSION: Various clinical features were associated with DR and ME. Additional epidemiological and biorepository-based studies using this cohort are being conducted to deepen our understanding of diabetic complications in Korea.

12.
Diabetes Metab J ; 40(3): 240-7, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27098506

RESUMEN

BACKGROUND: Gastrointestinal (GI) symptoms are common in patients with type 2 diabetes mellitus (T2DM). Rebamipide is an effective gastric cytoprotective agent, but there are few data on its usefulness in T2DM. The aim of this study is to evaluate the improvement of GI symptoms after rebamipide treatment in patients with T2DM. METHODS: Patients with T2DM and atypical GI symptoms were enrolled. They took rebamipide (100 mg thrice daily) for 12 weeks and filled out the diabetes bowel symptom questionnaire (DBSQ) before and after rebamipide treatment. The DBSQ consisted of 10 questions assessing the severity of GI symptoms by a 1 to 6 scoring system. Changes in the DBSQ scores before and after rebamipide treatment were analyzed to evaluate any improvements of GI symptoms. RESULTS: A total of 107 patients were enrolled, and 84 patients completed the study. The mean age was 65.0±7.8, 26 patients were male (24.8%), the mean duration of T2DM was 14.71±9.12 years, and the mean glycosylated hemoglobin level was 6.97%±0.82%. The total DBSQ score was reduced significantly from 24.9±8.0 to 20.4±7.3 before and after rebamipide treatment (P<0.001). The DBSQ scores associated with reflux symptoms, indigestion, nausea or vomiting, abdominal bloating or distension, peptic ulcer, abdominal pain, and constipation were improved after rebamipide treatment (P<0.05). However, there were no significant changes in symptoms associated with irritable bowel syndrome, diarrhea, and anal incontinence. No severe adverse events were reported throughout the study. CONCLUSION: Rebamipide treatment for 12 weeks improved atypical GI symptoms in patients with T2DM.

13.
Life Sci ; 92(13): 793-8, 2013 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-23454169

RESUMEN

AIMS: The aim of this study was to evaluate the therapeutic potential of the phenethyl isothiocyanate (PEITC) in Toll-like receptor (TLR) signaling pathways. MAIN METHODS: To evaluate the cytotoxic nature of PEITC in RAW 264.7 cells, cytotoxicity was determined using the MTS cell viability assay. RAW264.7 cells were transfected with a nuclear factor-κB (NF-κB), interferon ß (IFNß) PRDIII-I, or interferon inducible protein-10 (IP-10) luciferase plasmid and then luciferase enzyme activities were determined by luciferase assay. The expression of inducible nitric oxide synthase (iNOS) and phosphorylation of interferon regulatory factor 3 (IRF3) were determined by Western blotting. The levels of IP-10 were determined with culture medium by using an IP-10 enzyme-linked immunosorbent assay (ELISA) kit. KEY FINDINGS: PEITC suppressed the activation of IRF3 and the expression of IP-10 induced by lipopolysaccharide (LPS) or polyinosinic-polycytidylic acid (poly[I:C]). SIGNIFICANCE: TLRs play an important role in the induction of innate immune responses for host defense against invading microbial pathogens. PEITC found in cruciferous vegetables has an effect on treatment of many chronic diseases. Our results suggest that beneficial effects of PEITC on chronic inflammatory diseases are mediated through modulation of Toll-interleukin-1 receptor domain-containing adapter inducing interferon-ß (TRIF)-dependent signaling pathway of TLRs.


Asunto(s)
Proteínas Adaptadoras del Transporte Vesicular/inmunología , Antiinflamatorios/farmacología , Anticarcinógenos/farmacología , Isotiocianatos/farmacología , Receptores Toll-Like/inmunología , Animales , Antiinflamatorios/química , Anticarcinógenos/química , Línea Celular , Inflamación/tratamiento farmacológico , Inflamación/inmunología , Factor 3 Regulador del Interferón/inmunología , Isotiocianatos/química , Lipopolisacáridos/inmunología , Ratones , Monocitos/efectos de los fármacos , Monocitos/inmunología , FN-kappa B/inmunología , Poli I-C/inmunología , Transducción de Señal/efectos de los fármacos , Verduras/química
14.
PLoS One ; 6(12): e28308, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22162762

RESUMEN

Aberrant miR-21 expression is closely associated with cell proliferation, anti-apoptosis, migration, invasion, and metastasis in various cancers. However, the regulatory mechanism of miR-21 biogenesis is largely unknown. Here, we demonstrated that the tumor suppressor PTEN negatively regulates the expression of oncogenic miR-21 at the post-transcriptional level. Moreover, our results suggest that PTEN plays such a role through the indirect interaction with the Drosha complex. To elucidate how PTEN regulates pri- to pre-miR-21 processing, we attempted to find PTEN-interacting proteins and identified an RNA-regulatory protein, RNH1. Using the sensor to monitor pri-miR-21 processing, we demonstrated that RNH1 is necessary and sufficient for pri-miR-21 processing. Moreover, our results propose that the nuclear localization of RNH1 is important for this function. Further analysis showed that RNH1 directly interacts with the Drosha complex and that PTEN blocks this interaction. Taken together, these results suggest that the PTEN-mediated miR-21 regulation is achieved by inhibiting the interaction between the Drosha complex and RNH1, revealing previously unidentified role of PTEN in the oncogenic miR-21 biogenesis.


Asunto(s)
Proteínas Portadoras/metabolismo , Regulación Neoplásica de la Expresión Génica , Regulación de la Expresión Génica , MicroARNs/metabolismo , Neoplasias/metabolismo , Fosfohidrolasa PTEN/metabolismo , Ribonucleasa III/metabolismo , Núcleo Celular/metabolismo , Cromatografía Liquida/métodos , Proteínas Fluorescentes Verdes/metabolismo , Células HEK293 , Células HeLa , Humanos , Espectrometría de Masas/métodos , Microscopía Confocal/métodos , Procesamiento Postranscripcional del ARN
15.
J Nanosci Nanotechnol ; 11(7): 6580-3, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22121760

RESUMEN

The melting transition of nitrogen physisorbed on close-ended single-wall nanotube bundles was investigated using synchrotron X-ray diffraction measurements. The beta-nitrogen solid diffraction peak was observed above the coverage that corresponded to the monolayer and the average size of the nitrogen solid was approximately 30 A. The diffraction peak was surprisingly maintained above the triple point of the bulk nitrogen solid. The crystal structure of N2 changed from cubic N2 (beta-phase) to hexagonal N2 (beta-phase) at 35.61 K. The melting temperature of the nano-scale solid nitrogen in the experiment was between 80 K and 90 K, however, which is about 20 K higher than the melting temperature of normal bulk nitrogen. The observed extraordinary melting behavior of nitrogen might originate from a combination of two factors, i.e., the substrate field effect of the carbon nanotube surface (the interaction between the single walled carbon nanotubes and the adsorbates) and the capillary condensation. If the substrate field effect is especially prominent, the nitrogen molecules that were adsorbed mainly in the groove region would be under 1,100-Torr pressure from the nanotube bundles, compared to the corresponding melting temperature of the bulk beta-nitrogen solid under a high pressure.

16.
BMB Rep ; 44(7): 468-72, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21777518

RESUMEN

Toll-like receptors (TLRs) are pattern recognition receptors that recognize molecular structures derived from microbes and initiate innate immunity. TLRs have two downstream signaling pathways, the MyD88- and TRIF-dependent pathways. Dysregulated activation of TLRs is closely linked to increased risk of many chronic diseases. Previously, we synthesized fumaryl pyrrolidinone, (E)-isopropyl 4-oxo-4-(2-oxopyrrolidin-1- yl)-2-butenoate (IPOP), which contains a fumaric acid isopropyl ester and pyrrolidinone, and demonstrated that it inhibits the activation of nuclear factor kappa B by inhibiting the MyD88-dependent pathway of TLRs. However, the effect of IPOP on the TRIF-dependent pathway remains unknown. Here, we report the effect of IPOP on signal transduction via the TRIF-dependent pathway of TLRs. IPOP inhibited lipopolysaccharide- or polyinosinic-polycytidylic acid-induced interferon regulatory factor 3 activation, as well as interferon- inducible genes such as interferon inducible protein-10. These results suggest that IPOP can modulate the TRIF-dependent signaling pathway of TLRs, leading to decreased inflammatory gene expression.


Asunto(s)
Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Butiratos/farmacología , Fumaratos/farmacología , Pirrolidinonas/farmacología , Transducción de Señal/efectos de los fármacos , Receptores Toll-Like/metabolismo , Animales , Butiratos/química , Fumaratos/química , Humanos , Factor 3 Regulador del Interferón/metabolismo , Lipopolisacáridos/farmacología , Luciferasas/metabolismo , Ratones , FN-kappa B/metabolismo , Poli I-C/farmacología , Pirrolidinonas/química
17.
J Nanosci Nanotechnol ; 11(1): 286-90, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21446441

RESUMEN

We studied the effect of nano-tubular anodic TiO2 buffer layers on hydroxyapatite (HA) coating. The pulsed laser deposition (PLD) method was used to deposit HA on a well arranged nano-tubular anodic TiO2 (NT-ATO) buffer layer prepared by an electrochemical anodization technique. The surface morphology and chemical composition of HA coatings were characterized by using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and contact angle measurement. We found that crystalline HA coatings show well arranged porous morphologies with a favorable surface wettability. We also found that an anodic nano-tubular TiO2 buffer layer with a relatively short tube length shows a better coating morphology. The deposition process of HA on the nanotubular TiO2 buffer layer was also proposed.


Asunto(s)
Durapatita/química , Nanotubos/química , Titanio/química , Electrodos , Microscopía Electrónica de Rastreo , Nanotubos/ultraestructura , Tamaño de la Partícula , Porosidad , Espectrometría por Rayos X , Difracción de Rayos X
18.
J Nanosci Nanotechnol ; 11(1): 463-9, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21446477

RESUMEN

Ultralong ZnO nanorod arrays with a length of 10 microm were synthesized using a preheated hydrothermal-solution precursor, and their optical and electrical properties were studied using photoluminescence (PL) spectra and field effect transistors (FETs). The PL spectra showed ultraviolet, orange, and red emissions and had different temperature dependences with increasing temperature. The high-resolution photoluminescence spectra showed that the ultraviolet (UV) emission had different origins within different temperature ranges. The parameters describing the temperature dependence of the peak position shift, intensity, and full width at half maximum were evaluated using different models. After the fabrication of individual nanorod FETs, the ultralong ZnO NRs showed a clear n-type gate modulation with a typical electron concentration of 10(17) cm(-3) and a typical electron mobility of 35.7 cm2/V x s.

19.
Mol Cells ; 31(3): 261-5, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21347702

RESUMEN

Toll-like receptors (TLRs) play an important role in induction of innate immune responses for host defense against invading microbial pathogens. Microbial component engagement of TLRs can trigger the activation of myeloid differential factor 88 (MyD88)- and toll-interleukin-1 receptor domain-containing adapter inducing interferon-ß (TRIF)-dependent downstream signaling pathways. Parthenolide, an active ingredient of feverfew (Tanacetum parthenium), has been used for centuries to treat many chronic diseases. Parthenolide inhibits the MyD88-dependent pathway by inhibiting the activity of inhibitor-κB kinase. However, it is not known whether parthenolide inhibits the TRIF-dependent pathway. To evaluate the therapeutic potential of parthenolide, its effect on signal transduction via the TRIF-dependent pathway of TLRs induced by lipopolysaccharide (LPS) or polyinosinic-polycytidylic acid (poly [I:C]) was examined. Parthenolide inhibited nuclear factor-κB and interferon regulatory factor 3 activation induced by LPS or poly[I:C], and the LPS-induced phosphorylation of interferon regulatory factor 3 as well as interferon-inducible genes such as interferon inducible protein-10. These results suggest that parthenolide can modulate TRIF-dependent signaling pathways of TLRs, and may be the basis of effective therapeutics for chronic inflammatory diseases.


Asunto(s)
Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Macrófagos/metabolismo , Sesquiterpenos/farmacología , Transducción de Señal/efectos de los fármacos , Receptores Toll-Like/metabolismo , Animales , Línea Celular , Quimiocina CXCL10/metabolismo , Factor 3 Regulador del Interferón/metabolismo , Lipopolisacáridos/farmacología , Luciferasas/biosíntesis , Ratones , FN-kappa B/metabolismo , Fragmentos de Péptidos , Poli I-C/farmacología , Sesquiterpenos/química
20.
Int Immunopharmacol ; 11(1): 19-22, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20939996

RESUMEN

Toll-like receptors (TLRs) recognize molecular structures derived from microbes and initiate innate immunity. The stimulation of TLR4 by lipopolysaccharide (LPS) triggers the activation of the myeloid differential factor 88 (MyD88)-dependent and toll-interleukin-1 receptor domain-containing adapter inducing interferon-ß (TRIF)-dependent major downstream signaling pathways. Previously, we synthesized a fumaryl oxazolidinone derivative, 4-oxo-4-(2-oxo-oxazolidin-3-yl)-but-2-enoic acid ethyl ester (OSL07) and demonstrated that it inhibits activation of nuclear factor kappa B (NF-κB) by inhibiting the MyD88-dependent pathway of TLRs. TLR4 and the downstream signaling components are good therapeutic targets for many chronic inflammatory diseases. Here, it is investigated whether OSL07 modulates TLR4 downstream signaling pathways and what anti-inflammatory target in TLR4 signaling is regulated by OSL07. OSL07 inhibited LPS-induced NF-κB and interferon regulatory factor 3 activation by targeting TLR4 dimerization. These results suggest that OSL07 can modulate TLR4 signaling pathway leading to decreased inflammatory gene expression.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Fumaratos/farmacología , Oxazolidinonas/farmacología , Multimerización de Proteína/efectos de los fármacos , Receptor Toll-Like 4/antagonistas & inhibidores , Animales , Antiinflamatorios no Esteroideos/química , Western Blotting , Fumaratos/química , Células HEK293 , Humanos , Inmunoprecipitación , Factor 3 Regulador del Interferón/inmunología , Lipopolisacáridos/farmacología , Luciferasas/genética , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Estructura Molecular , FN-kappa B/genética , FN-kappa B/inmunología , Oxazolidinonas/química , Plásmidos , Transducción de Señal , Receptor Toll-Like 4/biosíntesis , Receptor Toll-Like 4/química , Transfección
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