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1.
FASEB J ; 35(3): e21391, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33565155

RESUMEN

Atherosclerosis is a chronic inflammatory disease of the arterial wall. It has been known that development of atherosclerosis is closely related to activation of tumor necrosis factor α (TNF-α). The objective of this study was to elucidate the effects of TNF-α blockade with brusatol on endothelial activation under pro-atherosclerotic conditions. To this end, we examined the effects of brusatol on TNF-α-induced intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) expression in human aortic endothelial cells (HAECs) using western blot and THP-1 adhesion assays. Brusatol induced a decrease in TNF-α-induced ICAM-1 and VCAM-1 expression through inhibiting TNFR1 expression, leading to suppression of endothelial inflammation independently of the NRF2 (nuclear factor erythroid 2-related factor 2) pathway. The mechanism underlying brusatol-induced TNF receptor 1 (TNFR1) inhibition was investigated with the aid of protein synthesis, co-immunoprecipitation, and cytokine arrays. Notably, brusatol inhibited TNFR1 protein synthesis and suppressed both the canonical nuclear factor kappa-light-chain-enhancer of activated B cell (NF-κB) signaling pathway and TNF-α-induced cytokine secretion. We further tested the functional effect of brusatol on atherosclerosis development in vivo using two different atherosclerosis mouse models, specifically, acute partial carotid ligation and conventional chronic high-fat diet-fed mouse models. Administration of brusatol led to significant suppression of atherosclerosis development in both mouse models. Our finding that brusatol prevents atherosclerosis via inhibition of TNFR1 protein synthesis supports the potential of downregulation of cell surface TNFR1 as an effective therapeutic approach to inhibit development of atherosclerosis.


Asunto(s)
Aterosclerosis/prevención & control , Cuassinas/uso terapéutico , Receptores Tipo I de Factores de Necrosis Tumoral/antagonistas & inhibidores , Animales , Células Cultivadas , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Humanos , Molécula 1 de Adhesión Intercelular/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Complejo de la Endopetidasa Proteasomal/fisiología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Molécula 1 de Adhesión Celular Vascular/genética
2.
FASEB J ; 34(8): 10316-10328, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32530114

RESUMEN

Cellular senescence can be triggered by various intrinsic and extrinsic stimuli. We previously reported that silencing of 3'-phosphoadenosine 5'-phosphosulfate synthetase 2 (PAPSS2) induces cellular senescence through augmented fibroblast growth factor receptor 1 (FGFR1) signaling. However, the exact molecular mechanism connecting heparan sulfation and cellular senescence remains unclear. Here, we investigated the potential involvement of heparan sulfate proteoglycans (HSPGs) in augmented FGFR1 signaling and cellular senescence. Depletion of several types of HSPGs revealed that cells depleted of syndecan 1 (SDC1) exhibited typical senescence phenotypes, and those depleted of PAPSS2-, SDC1-, or heparan sulfate 2-O sulfotransferase 1 (HS2ST1) showed decreased FGFR1 internalization along with hyperresponsiveness to and prolonged activation of fibroblast growth factor 2 (FGF2)-stimulated FGFR1- v-akt murine thymoma viral oncogene homolog (AKT) signaling. Clathrin- and caveolin-mediated FGFR1 endocytosis contributed to cellular senescence through the FGFR1-AKT-p53-p21 signaling pathway. Dynasore treatment triggered senescence phenotypes, augmented FGFR1-AKT-p53-p21 signaling, and decreased SDC1 expression. Finally, the replicatively and prematurely senescent cells were characterized by decreases of SDC1 expression and FGFR1 internalization, and an increase in FGFR1-AKT-p53-p21 signaling. Together, our results demonstrate that properly sulfated SDC1 plays a critical role in preventing cellular senescence through the regulation of FGFR1 endocytosis.


Asunto(s)
Senescencia Celular/fisiología , Endocitosis/fisiología , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/metabolismo , Sulfatos/metabolismo , Sindecano-1/metabolismo , Caveolinas/metabolismo , Línea Celular , Línea Celular Tumoral , Clatrina/metabolismo , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Heparitina Sulfato/metabolismo , Humanos , Células MCF-7 , Transducción de Señal/fisiología
3.
Immunity ; 36(5): 769-81, 2012 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-22608497

RESUMEN

The coordination of nutrient and energy availability with cell growth and division is essential for proper immune cell development and function. By using a chemical mutagenesis strategy in mice, we identified a pedigree that has a complete block in B cell development at the pre-B cell stage resulting from a deletion in the Fnip1 gene. Enforced expression of an immunoglobulin transgene failed to rescue B cell development. Whereas essential pre-B cell signaling molecules were activated normally in Fnip1-null pre-B cells, the metabolic regulators AMPK and mTOR were dysregulated, resulting in excessive cell growth and enhanced sensitivity to apoptosis in response to metabolic stress (pre-B cell receptor crosslinking, oncogene activation). These results indicate that Folliculin-interacting protein 1 (Fnip1) is vital for B cell development and metabolic homeostasis and reveal a metabolic checkpoint that may ensure that pre-B cells have sufficient metabolic capacity to support division, while limiting lymphomagenesis caused by deregulated growth.


Asunto(s)
Linfocitos B/citología , Linfocitos B/metabolismo , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Diferenciación Celular/genética , Estrona/genética , Estrona/metabolismo , Quinasas de la Proteína-Quinasa Activada por el AMP , Animales , Apoptosis/genética , División Celular/genética , Hematopoyesis/genética , Cadenas Pesadas de Inmunoglobulina/genética , Cadenas Pesadas de Inmunoglobulina/metabolismo , Ratones , Ratones Transgénicos , Células Precursoras de Linfocitos B/metabolismo , Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Transducción de Señal/genética , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo
4.
J Immunol ; 203(11): 2899-2908, 2019 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-31676673

RESUMEN

Folliculin interacting protein 1 (Fnip1) is a cytoplasmic protein originally discovered through its interaction with the master metabolic sensor 5' AMP-activated protein kinase (AMPK) and Folliculin, a protein mutated in individuals with Birt-Hogg-Dubé Syndrome. In response to low energy, AMPK stimulates catabolic pathways such as autophagy to enhance energy production while inhibiting anabolic pathways regulated by the mechanistic target of rapamycin complex 1 (mTORC1). We previously found that constitutive disruption of Fnip1 in mice resulted in a lack of peripheral B cells because of a block in B cell development at the pre-B cell stage. Both AMPK and mTORC1 were activated in Fnip1-deficient B cell progenitors. In this study, we found inappropriate mTOR localization at the lysosome under nutrient-depleted conditions. Ex vivo lysine or arginine depletion resulted in increased apoptosis. Genetic inhibition of AMPK, inhibition of mTORC1, or restoration of cell viability with a Bcl-xL transgene failed to rescue B cell development in Fnip1-deficient mice. Fnip1-deficient B cell progenitors exhibited increased nuclear localization of transcription factor binding to IgHM enhancer 3 (TFE3) in developing B cells, which correlated with an increased expression of TFE3-target genes, increased lysosome numbers and function, and increased autophagic flux. These results indicate that Fnip1 modulates autophagy and energy response pathways in part through the regulation of AMPK, mTORC1, and TFE3 in B cell progenitors.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Linfocitos B/metabolismo , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Proteínas Portadoras/metabolismo , Homeostasis , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Animales , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados
5.
Anal Chem ; 92(7): 4917-4925, 2020 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-32153189

RESUMEN

It is highly challenging to develop fast and sensitive fluorescent methods for monitoring organic mercury in purely aqueous solutions as well as live cells. Especially, selective fluorescent detection of methylmercury over inorganic mercury ions has not been reported. We developed a fast and sensitive fluorescent detection method for Hg2+ ions as well as methylmercury using an amino acid-based fluorescent probe (1) and SDS micelles. The fluorescent probe in SDS micelles detected sensitively and selectively Hg2+ ions and methylmercury among 16 metal ions in purely aqueous solution by the enhancement of the red emission at 575 nm, and the detection of methylmercury was completed within 1 min. The probe in SDS micelles with EDTA showed highly sensitive and selective turn on detection for methylmercury over Hg2+. The limit of detection was 9.1 nM for Hg2+ (1.8 ppb, R2 = 0.989) and 206 nM for CH3Hg+ (R2 = 0.997). 1 rapidly penetrated live cells and detected intracellular Hg2+ ions as well as CH3Hg+ by the enhancement of both red emissions and green emissions. Subsequent treatment of EDTA into the cell confirmed the selective detection of methylmercury in the cells. The present work indicated that the fluorescent probe with micelle systems provided a fast, sensitive, and selective detection method for monitoring inorganic mercury as well as methyl mercury.


Asunto(s)
Colorantes Fluorescentes/química , Compuestos de Metilmercurio/análisis , Contaminantes Químicos del Agua/química , Células A549 , Humanos , Micelas , Conformación Molecular , Imagen Óptica , Soluciones , Espectrometría de Fluorescencia
6.
Bioconjug Chem ; 31(1): 43-50, 2020 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-31841634

RESUMEN

The stimuli-responsive conformational transformation of peptides possessing a constrained form triggered by specific biological microenvironment would provide an effective strategy for the development of highly specific peptide therapeutics. Here, we developed a peptide containing a cytotoxic helical KLA sequence with therapeutic specificity through the use of stimuli-responsive conformational transformation. The KLA peptide is modified to form a cyclic structure to allow for constrained helicity that confers low cytotoxicity. The modified KLA peptide is electrostatically complexed to hyaluronic acid to facilitate enhanced endocytosis into the cancer cells. After endocytosis, the peptide is released from the complex into the cellular cytoplasm by hyaluronidases on the surface of the cellular membrane. Specific intracellular stimuli then trigger the release of the strain that suppresses peptide helicity, and the inherent helical conformation of the KLA peptide is restored. Therefore, the stimuli-responsive conformational transformation of a peptide from low to high helicity selectively induces cell death by disruption of the plasma and mitochondrial membrane.


Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Descubrimiento de Drogas , Péptidos y Proteínas de Señalización Intercelular/química , Péptidos y Proteínas de Señalización Intercelular/farmacología , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Humanos , Membranas Mitocondriales/efectos de los fármacos , Modelos Moleculares , Neoplasias/tratamiento farmacológico , Conformación Proteica en Hélice alfa
7.
Nucleic Acids Res ; 45(11): 6894-6910, 2017 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-28472401

RESUMEN

RNA-binding proteins (RBPs) are involved in mRNA splicing, maturation, transport, translation, storage and turnover. Here, we identified ACOT7 mRNA as a novel target of human WIG1. ACOT7 mRNA decay was triggered by the microRNA miR-9 in a WIG1-dependent manner via classic recruitment of Argonaute 2 (AGO2). Interestingly, AGO2 was also recruited to ACOT7 mRNA in a WIG1-dependent manner in the absence of miR-9, which indicates an alternative model whereby WIG1 controls AGO2-mediated gene silencing. The WIG1-AGO2 complex attenuated translation initiation via an interaction with translation initiation factor 5B (eIF5B). These results were confirmed using a WIG1 tethering system based on the MS2 bacteriophage coat protein and a reporter construct containing an MS2-binding site, and by immunoprecipitation of WIG1 and detection of WIG1-associated proteins using liquid chromatography-tandem mass spectrometry. We also identified WIG1-binding motifs using photoactivatable ribonucleoside-enhanced crosslinking and immunoprecipitation analyses. Altogether, our data indicate that WIG1 governs the miRNA-dependent and the miRNA-independent recruitment of AGO2 to lower the stability of and suppress the translation of ACOT7 mRNA.


Asunto(s)
Proteínas Argonautas/fisiología , Proteínas Portadoras/fisiología , MicroARNs/fisiología , Proteínas Nucleares/fisiología , Interferencia de ARN , ARN Mensajero/metabolismo , Regiones no Traducidas 3' , Secuencia de Bases , Sitios de Unión , Factores Eucarióticos de Iniciación/metabolismo , Células HCT116 , Células HEK293 , Humanos , Secuencias Invertidas Repetidas , Células MCF-7 , Unión Proteica , Biosíntesis de Proteínas , Dominios Proteicos , Estabilidad del ARN , ARN Mensajero/genética , Proteínas de Unión al ARN
8.
Int J Mol Sci ; 20(18)2019 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-31491980

RESUMEN

5-Fluorouracil (5-FU) is an important chemotherapeutic agent for the systemic treatment of colorectal cancer (CRC), but its effectiveness against CRC is limited by increased 5-FU resistance caused by the hypoxic tumor microenvironment. The purpose of our study was to assess the feasibility of using quinacrine (QC) to increase the efficacy of 5-FU against CRC cells under hypoxic conditions. QC reversed the resistance to 5-FU induced by hypoxia in CRC cell lines, as determined using ATP-Glo cell viability assays and clonogenic survival assays. Treatment of cells with 5-FU under hypoxic conditions had no effect on the expression of nuclear factor (erythroid-derived 2)-like 2 (Nrf2), a regulator of cellular resistance to oxidative stress, whereas treatment with QC alone or in combination with 5-FU reduced Nrf2 expression in all CRC cell lines tested. Overexpression of Nrf2 effectively prevented the increase in the number of DNA double-strand breaks induced by QC alone or in combination with 5-FU. siRNA-mediated c-Jun N-terminal kinase-1 (JNK1) knockdown inhibited the QC-mediated Nrf2 degradation in CRC cells under hypoxic conditions. The treatment of CRC xenografts in mice with the combination of QC and 5-FU was more effective in suppressing tumor growth than QC or 5-FU alone. QC increases the susceptibility of CRC cells to 5-FU under hypoxic conditions by enhancing JNK1-dependent Nrf2 degradation.


Asunto(s)
Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Resistencia a Antineoplásicos/genética , Fluorouracilo/farmacología , Hipoxia/genética , Hipoxia/metabolismo , Factor 2 Relacionado con NF-E2/genética , Quinacrina/farmacología , Animales , Línea Celular Tumoral , Neoplasias Colorrectales/tratamiento farmacológico , Modelos Animales de Enfermedad , Fluorouracilo/uso terapéutico , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , Modelos Biológicos , Factor 2 Relacionado con NF-E2/metabolismo , Estadificación de Neoplasias , Proteolisis , Ensayos Antitumor por Modelo de Xenoinjerto
9.
Biochem Biophys Res Commun ; 495(1): 212-216, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29113799

RESUMEN

Hypoxia is a common characteristic of many types of solid tumors. Intratumoral hypoxia selects for tumor cells that survive in a low oxygen environment, undergo epithelial-mesenchymal transition, are more motile and invasive, and show gene expression changes driven by hypoxia-inducible factor-1α (HIF-1α) activation. Therefore, targeting HIF-1α is an attractive strategy for disrupting multiple pathways crucial for tumor growth. In the present study, we demonstrated that hypoxia increases the S-glutathionylation of HIF-1α and its protein levels in colon cancer cells. This effect is significantly prevented by decreasing oxidized glutathione as well as glutathione depletion, indicating that S-glutathionylation and the formation of protein-glutathione mixed disulfides is related to HIF-1α protein levels. Moreover, colon cancer cells expressing glutaredoxin 1 are resistant to inducing HIF-1α and expressing hypoxia-responsive genes under hypoxic conditions. Therefore, S-glutathionylation of HIF-1α induced by tumor hypoxia may be a novel therapeutic target for the development of new drugs.


Asunto(s)
Neoplasias del Colon/metabolismo , Glutatión/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Hipoxia/metabolismo , Hipoxia de la Célula , Neoplasias del Colon/complicaciones , Neoplasias del Colon/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Hipoxia/complicaciones , Hipoxia/genética , Oxidación-Reducción
10.
J Immunol ; 197(6): 2250-60, 2016 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-27521345

RESUMEN

Mechanistic target of rapamycin (mTOR) is a serine-threonine kinase that coordinates nutrient and growth factor availability with cellular growth, division, and differentiation. Studies examining the roles of mTOR signaling in immune function revealed critical roles for mTOR in regulating T cell differentiation and function. However, few studies have investigated the roles of mTOR in early B cell development. In this study, we found that mTOR is highly activated during the pro- and pre-B stages of mouse B cell development. Conditional disruption of the mTOR coactivating protein Raptor in developing mouse B cells resulted in a developmental block at the pre-B cell stage, with a corresponding lack of peripheral B cells and loss of Ag-specific Ab production. Pre-B cell survival and proliferation were significantly reduced in Raptor-deficient mice. Forced expression of a transgenic BCR or a BclxL transgene on Raptor-deficient B cells failed to rescue B cell development, suggesting that pre-BCR signaling and B cell survival are impaired in a BclxL-independent manner. Raptor-deficient pre-B cells exhibited significant decreases in oxidative phosphorylation and glycolysis, indicating that loss of mTOR signaling in B cells significantly impairs cellular metabolic capacity. Treatment of mice with rapamycin, an allosteric inhibitor of mTOR, recapitulated the early B cell developmental block. Collectively, our data reveal a previously uncharacterized role for mTOR signaling in early B cell development, survival, and metabolism.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Complejos Multiproteicos/genética , Complejos Multiproteicos/metabolismo , Células Precursoras de Linfocitos B/fisiología , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Animales , Proliferación Celular , Supervivencia Celular , Glucólisis/efectos de los fármacos , Diana Mecanicista del Complejo 1 de la Rapamicina , Ratones , Fosforilación/efectos de los fármacos , Células Precursoras de Linfocitos B/efectos de los fármacos , Células Precursoras de Linfocitos B/inmunología , Células Precursoras de Linfocitos B/metabolismo , Proteína Reguladora Asociada a mTOR , Transducción de Señal , Sirolimus/farmacología , Serina-Treonina Quinasas TOR/deficiencia , Factores de Transcripción , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
11.
Chemistry ; 23(67): 16966-16971, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-29077239

RESUMEN

Utilizing stimuli-responsive conformational transformation of a cyclic peptide as a gatekeeper for mesoporous nanocarriers has several advantages such as facile introduction of targeting capabilities, low enzymatic degradation during blood circulation and enhanced specific binding to selected cells. In this report, a Asn-Gly-Arg (NGR)-containing dual-functional cyclic peptide gatekeeper on the surface of mesoporous nanocarrier is prepared not only for active targeting of the aminopeptidase N (APN) expressed on cancer cells but also stimuli-responsive intracellular drug release triggered by a glutathione (GSH)-induced conformational transformation of the peptide gatekeeper. The peptide gatekeeper on the surface of nanocarriers exhibits on-off gatekeeping by conformational transformation triggered by intracellular glutathione of the cancer cells. H1299 cells (high APN expression) showed greater uptake of the nanocarrier by endocytosis and higher apoptosis than A549 cells (low APN expression).


Asunto(s)
Antineoplásicos/farmacología , Antígenos CD13/metabolismo , Doxorrubicina/farmacología , Nanocápsulas/química , Péptidos Cíclicos/química , Dióxido de Silicio/química , Antineoplásicos/química , Apoptosis , Línea Celular Tumoral , Supervivencia Celular , Preparaciones de Acción Retardada , Doxorrubicina/química , Liberación de Fármacos , Glutatión/química , Humanos , Conformación Molecular , Oligopéptidos/química , Tamaño de la Partícula , Porosidad , Propiedades de Superficie
12.
Proc Natl Acad Sci U S A ; 111(19): 7066-71, 2014 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-24785297

RESUMEN

Folliculin-interacting protein 1 (Fnip1) is an adaptor protein that physically interacts with AMPK, an energy-sensing kinase that stimulates mitochondrial biogenesis and autophagy in response to low ATP, while turning off energy consumption mediated by mammalian target of rapamycin. Previous studies with Fnip1-null mice revealed that Fnip1 is essential for pre-B-cell development. Here we report a critical role of Fnip1 in invariant natural killer T (iNKT) cell development. Thymic iNKT development in Fnip1(-/-) mice was arrested at stage 2 (NK1.1(-)CD44(+)) but development of CD4, CD8, γδ T-cell, and NK cell lineages proceeded normally. Enforced expression of a Vα14Jα18 iNKT TCR transgene or loss of the proapoptotic protein Bim did not rescue iNKT cell maturation in Fnip1(-/-) mice. Whereas most known essential transcription factors for iNKT cell development were represented normally, Fnip1(-/-) iNKT cells failed to down-regulate Promyelocytic leukemia zinc finger compared with their WT counterparts. Moreover, Fnip1(-/-) iNKT cells contained hyperactive mTOR and reduced mitochondrial number despite lower ATP levels, resulting in increased sensitivity to apoptosis. These results indicate that Fnip1 is vital for iNKT cell development by maintaining metabolic homeostasis in response to metabolic stress.


Asunto(s)
Proteínas Portadoras/inmunología , Proteínas Portadoras/metabolismo , Metabolismo Energético/inmunología , Células T Asesinas Naturales/inmunología , Células T Asesinas Naturales/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Síndrome de Birt-Hogg-Dubé/inmunología , Síndrome de Birt-Hogg-Dubé/metabolismo , Linfocitos T CD4-Positivos/citología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Proteínas Portadoras/genética , Supervivencia Celular/inmunología , Femenino , Homeostasis/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Células T Asesinas Naturales/citología , Receptores de Antígenos de Linfocitos T gamma-delta/inmunología , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Serina-Treonina Quinasas TOR/inmunología , Serina-Treonina Quinasas TOR/metabolismo , Timo/citología , Timo/inmunología
13.
Anal Chem ; 88(6): 3333-40, 2016 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-26872241

RESUMEN

A fluorescent peptidyl chemosensor for the detection of heavy metal ions in aqueous solution as well as in cells was synthesized on the basis of the peptide receptor for the metal ions using an aggregation-induced emission fluorophore. The peptidyl chemosensor (1) bearing tetraphenylethylene fluorophore showed an exclusively selective turn-on response to Hg(2+) among 16 metal ions in aqueous buffered solution containing NaCl. The peptidyl chemosensor complexed Hg(2+) ions and then aggregated in aqueous buffered solution, resulting in the significant enhancement (OFF-On) of emissions at around 470 nm. The fluorescent sensor showed a highly sensitive response to Hg(2+), and about 1.0 equiv of Hg(2+) was enough for the saturation of the emission intensity change. The detection limit (5.3 nM, R(2) = 0.99) of 1 for Hg(2+) ions was lower than the maximum allowable level of Hg(2+) in drinking water by EPA. Moreover, the peptidyl chemosensor penetrated live cells and detected intracellular Hg(2+) ions by the turn-on response.


Asunto(s)
Metales Pesados/análisis , Péptidos/química , Fluorescencia , Concentración de Iones de Hidrógeno , Límite de Detección , Soluciones , Espectrometría de Fluorescencia , Agua
14.
Nanomedicine ; 12(5): 1219-29, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26945975

RESUMEN

The therapeutic efficacy of intranasal iNOS siRNA delivery was investigated in the postischemic rat brain after encapsulating on in gelatin nanoparticles (GNPs; diameter 188.0 ± 60.9 nm) cross-linked with 0.0667% glutaraldehyde (GA). Intranasally delivered GNPs were found in extracellular and intracellular compartments of many brain regions, including the olfactory bulb, cerebral cortex, and striatum at 1 hour after infusion and continued to be detected for days. Infarct volumes were markedly suppressed (maximal reduction to 42.1 ± 2.6%) at 2 days after 60 minutes of middle cerebral artery occlusion (MCAO) when iNOS siRNA/GNPs were delivered at 6 hours post-MCAO. In addition, this protective effect was manifested by reductions in neurological and behavioral deficits that were sustained for 2 weeks. Therapeutic potency of iNOS siRNA/GNPs was significantly greater and sustained longer than that of bare siRNA and prolonged and efficient iNOS by iNOS siRNA/GNP is responsible for the robust neuroprotective effect.


Asunto(s)
Nanopartículas , Fármacos Neuroprotectores/administración & dosificación , ARN Interferente Pequeño/administración & dosificación , Administración Intranasal , Animales , Encéfalo , Gelatina , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Ratas
15.
Xenotransplantation ; 22(4): 249-59, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26174875

RESUMEN

BACKGROUND: Hepatocyte transplantation is a promising therapy for acute liver failure. Cell therapy using xenogeneic sources has emerged as an alternative treatment for patients with organ failure due to the shortage of transplantable human organs. The purpose of this study was to improve the survival of mice with acute liver failure by transplanting encapsulated neonatal pig re-aggregated liver cells (NPRLC). METHODS: Liver injury was induced in C57/BL6 male mice by the injection of 600 mg/kg of acetaminophen. Xenogeneic liver cells were isolated from a neonatal pig and processed via re-aggregation and encapsulation to improve the efficiency of the xenogeneic liver cell transplantation. The neonatal pig liver showed abnormal lobule structure. Isolated cells were re-aggregated and intraperitoneally transplanted into acute liver failure mice models. RESULTS: Re-aggregated cells showed significantly enhanced viability and significantly greater synthesis of albumin and urea than cells cultured in monolayers. Further, we observed improved serum levels of ALT/AST, and the survival rate of mice with acute liver failure was improved by the intraperitoneal transplantation of encapsulated hepatocytes (48,000 equivalent (Eq) per mouse). CONCLUSIONS: This study shows that using encapsulated NPRLCs improves the efficacy of xenogeneic liver cell transplantation for the treatment of mice with acute liver failure. Therefore, this may be a good strategy for bridge therapy for the treatment of acute liver failure in humans.


Asunto(s)
Hepatocitos/trasplante , Fallo Hepático Agudo/terapia , Trasplante Heterólogo/métodos , Acetaminofén/toxicidad , Albúminas/biosíntesis , Animales , Animales Recién Nacidos , Agregación Celular , Supervivencia Celular , Células Cultivadas , Modelos Animales de Enfermedad , Supervivencia de Injerto , Hepatocitos/citología , Hepatocitos/metabolismo , Humanos , Fallo Hepático Agudo/inducido químicamente , Masculino , Ratones , Ratones Endogámicos C57BL , Esferoides Celulares/trasplante , Sus scrofa , Porcinos , Porcinos Enanos , Urea/metabolismo
16.
Ann Otol Rhinol Laryngol ; 124(1): 62-7, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25048959

RESUMEN

OBJECTIVE: Ethanol ablation has been known as an effective, easy, and safe treatment of cystic thyroid lesions. The objective of the present study was to evaluate efficacy of ethanol ablation as a minimally invasive management of thyroglossal duct cyst (TGDC). METHODS: Between January 2012 and July 2013, 9 TGDC patients were diagnosed and treated with ethanol ablation. We evaluated the treatment outcomes with the change of volume reduction and the improvement of symptomatic and cosmetic complaints and complications. RESULTS: Initial mean tumor volume was 8.9 mL (range, 0.2-36.9 mL) in ultrasonography. The mean number of the treatment sessions was 1.7 (range, 1-3 sessions). At last follow-up, the mean volume of the treated thyroglossal duct cyst decreased significantly from 8.9 mL to 1.9 mL (P = .019; volume reduction rate = 76.6%). Treatment success rate was 77.8% (7/9). Mean symptoms and cosmetic-grading scores improved from 5.2 to 3.1 and from 5.3 to 3.1 (P = .062). No significant complications were observed during follow-up. CONCLUSION: Ethanol ablation is a feasible and convenient procedure without surgical scars and hospitalization for TGDC patients. Favorable outcomes can be achieved without significant complications.


Asunto(s)
Etanol/administración & dosificación , Escleroterapia/métodos , Solventes/administración & dosificación , Quiste Tirogloso/terapia , Adolescente , Adulto , Estudios de Cohortes , Femenino , Humanos , Inyecciones Intralesiones , Masculino , Persona de Mediana Edad , Quiste Tirogloso/patología , Resultado del Tratamiento , Adulto Joven
17.
J Korean Med Sci ; 30(7): 991-4, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26130966

RESUMEN

Pancreatic islet transplantation is a physiologically advantageous and minimally invasive procedure for the treatment of type 1 diabetes mellitus. Here, we describe the first reported case of successful allogeneic islet transplantation alone, using single-donor, marginal-dose islets in a Korean patient. A 59-yr-old patient with type 1 diabetes mellitus, who suffered from recurrent severe hypoglycemia, received 4,163 islet equivalents/kg from a single brain-death donor. Isolated islets were infused intraportally without any complications. The immunosuppressive regimen was based on the Edmonton protocol, but the maintenance dosage was reduced because of mucositis and leukopenia. Although insulin independence was not achieved, the patient showed stabilized blood glucose concentration, reduced insulin dosage and reversal of hypoglycemic unawareness, even with marginal dose of islets and reduced immunosuppressant. Islet transplantation may successfully improve endogenous insulin production and glycemic stability in subjects with type 1 diabetes mellitus.


Asunto(s)
Diabetes Mellitus Tipo 1/cirugía , Hipoglucemia/cirugía , Trasplante de Islotes Pancreáticos/métodos , Islotes Pancreáticos/cirugía , Glucemia/análisis , Femenino , Humanos , Terapia de Inmunosupresión/métodos , Inmunosupresores/uso terapéutico , Islotes Pancreáticos/fisiología , Persona de Mediana Edad , República de Corea , Donantes de Tejidos
18.
J Craniofac Surg ; 26(4): 1159-62, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26080148

RESUMEN

The purpose of this study was to determine the cephalometric variables that can predict the future need for orthognathic surgery or distraction osteogenesis in Korean male patients with nonsyndromic cleft lip and alveolus (CLA) and unilateral (UCLP) and bilateral cleft lip and palate (BCLP). A total of 131 patients who were treated by one surgeon and one orthodontist using identical protocol were divided into CLA group (n = 35), UCLP group (n = 56), and BCLP group (n = 40). Lateral cephalograms were taken before secondary alveolar bone graft (T0; mean age, 9.3 years) and at the minimum of 15 years of age (T1; mean age, 17.3 years). The cephalometric variables of these cephalograms were measured. At T1 stage, 3 cephalometric criteria were used to divide the subjects into surgery and nonsurgery groups (ANB ≤ -3 degrees; Wits appraisal ≤ -5 mm; Harvold unit difference ≥ 34 mm for surgery group). The feature wrapping method was used to determine the cephalometric variables at T0 stage for a prediction model. At T1 stage, 27 (20.6%) of 131 subjects required surgical intervention to correct their sagittal skeletal discrepancies. Frequency was significantly different among the CLA, UCLP, and BCLP groups (8.5%, 21.4%, and 30.0%, respectively; P < 0.05; [CLA, UCLP] < [UCLP, BCLP]). A total of 10 cephalometric variables of T0 stage were selected as predictors, and weighted classification accuracy was 77.3%. The frequency of surgical intervention increased with cleft severity. Ten cephalometric variables might be regarded as effective predictors of the future need for surgery to correct their sagittal skeletal discrepancies.


Asunto(s)
Injerto de Hueso Alveolar/métodos , Labio Leporino/cirugía , Fisura del Paladar/cirugía , Toma de Decisiones , Cirugía Ortognática/métodos , Osteogénesis por Distracción/métodos , Adolescente , Cefalometría , Niño , Labio Leporino/diagnóstico , Fisura del Paladar/diagnóstico , Humanos , Masculino , Pronóstico
19.
J Craniofac Surg ; 26(8): 2357-63, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26594968

RESUMEN

The aim of this study was to investigate the pattern, amount, and distribution of postsurgical relapse in skeletal Class III patients treated with two-jaw surgery (TJS) using conventional three-stage method (CTM) and surgery-first approach (SFA). A total of 38 patients who underwent the nonextraction approach and TJS (LeFort I posterior impaction and mandibular setback) were divided into CTM and SFA groups (all n = 19/group). Lateral cephalograms were taken before treatment (T0), at 1 month before surgery (T1), immediately after surgery (T2), and at debonding (T3) for CTM patients and at T0, T2, and T3 stages for SFA patients. Cephalometric measurements and statistical analyses were performed. There were no significant differences in the cephalometric variables at all stages except maxillary incisor inclination (U1-UOP) and overbite at T0 between 2 groups. They also did not exhibit significant differences in the amounts of surgical movement except for advancement of the maxilla. The mandible in both groups was rotated slightly clockwise by surgery and counterclockwise during T2-T3 without a significant difference. Distribution of cases with "high relapse" (>30%) and "low relapse" (<30%) of the mandible differed for 2 groups (P < 0.05). SFA group had more "high relapse" cases than CTM group (57.9% versus 26.3%). Postsurgical relapse of the mandible had a positive relationship with the amount of mandibular setback in SFA group (P < 0.01) and clockwise rotation of the proximal segment of the mandible in both groups (P < 0.05 and P < 0.01). The results suggest that SFA might be an effective alternative to CTM if the cause of "high relapse" including amounts of mandibular setback and clockwise rotation of the proximal segment of the mandible during surgery can be controlled.


Asunto(s)
Maloclusión de Angle Clase III/cirugía , Mandíbula/cirugía , Maxilar/cirugía , Cirugía Ortognática/métodos , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Adolescente , Adulto , Cefalometría , Femenino , Humanos , Masculino , Osteotomía Le Fort , Recurrencia , Reoperación , Adulto Joven
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