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1.
FASEB J ; 35(3): e21391, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33565155

RESUMO

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.


Assuntos
Aterosclerose/prevenção & controle , Quassinas/uso terapêutico , Receptores Tipo I de Fatores de Necrose Tumoral/antagonistas & inibidores , Animais , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Complexo de Endopeptidases do Proteassoma/fisiologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Molécula 1 de Adesão de Célula Vascular/genética
2.
FASEB J ; 34(8): 10316-10328, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32530114

RESUMO

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.


Assuntos
Senescência Celular/fisiologia , Endocitose/fisiologia , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Sulfatos/metabolismo , Sindecana-1/metabolismo , Caveolinas/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Clatrina/metabolismo , Fator 2 de Crescimento de Fibroblastos/metabolismo , Heparitina Sulfato/metabolismo , Humanos , Células MCF-7 , Transdução de Sinais/fisiologia
3.
Immunity ; 36(5): 769-81, 2012 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-22608497

RESUMO

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.


Assuntos
Linfócitos B/citologia , Linfócitos B/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Diferenciação Celular/genética , Estrona/genética , Estrona/metabolismo , Quinases Proteína-Quinases Ativadas por AMP , Animais , Apoptose/genética , Divisão Celular/genética , Hematopoese/genética , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/metabolismo , Camundongos , Camundongos Transgênicos , Células Precursoras de Linfócitos B/metabolismo , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Transdução de Sinais/genética , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
4.
J Immunol ; 203(11): 2899-2908, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31676673

RESUMO

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.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Linfócitos B/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Proteínas de Transporte/metabolismo , Homeostase , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Animais , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
5.
Anal Chem ; 92(7): 4917-4925, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32153189

RESUMO

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.


Assuntos
Corantes Fluorescentes/química , Compostos de Metilmercúrio/análise , Poluentes Químicos da Água/química , Células A549 , Humanos , Micelas , Conformação Molecular , Imagem Óptica , Soluções , Espectrometria de Fluorescência
6.
Bioconjug Chem ; 31(1): 43-50, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31841634

RESUMO

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.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Descoberta de Drogas , Peptídeos e Proteínas de Sinalização Intercelular/química , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Membranas Mitocondriais/efeitos dos fármacos , Modelos Moleculares , Neoplasias/tratamento farmacológico , Conformação Proteica em alfa-Hélice
7.
Nucleic Acids Res ; 45(11): 6894-6910, 2017 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-28472401

RESUMO

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.


Assuntos
Proteínas Argonautas/fisiologia , Proteínas de Transporte/fisiologia , MicroRNAs/fisiologia , Proteínas Nucleares/fisiologia , Interferência de RNA , RNA Mensageiro/metabolismo , Regiões 3' não Traduzidas , Sequência de Bases , Sítios de Ligação , Fatores de Iniciação em Eucariotos/metabolismo , Células HCT116 , Células HEK293 , Humanos , Sequências Repetidas Invertidas , Células MCF-7 , Ligação Proteica , Biossíntese de Proteínas , Domínios Proteicos , Estabilidade de RNA , RNA Mensageiro/genética , Proteínas de Ligação a RNA
8.
Int J Mol Sci ; 20(18)2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31491980

RESUMO

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.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Fluoruracila/farmacologia , Hipóxia/genética , Hipóxia/metabolismo , Fator 2 Relacionado a NF-E2/genética , Quinacrina/farmacologia , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Modelos Animais de Doenças , Fluoruracila/uso terapêutico , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Modelos Biológicos , Fator 2 Relacionado a NF-E2/metabolismo , Estadiamento de Neoplasias , Proteólise , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Biochem Biophys Res Commun ; 495(1): 212-216, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29113799

RESUMO

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.


Assuntos
Neoplasias do Colo/metabolismo , Glutationa/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia/metabolismo , Hipóxia Celular , Neoplasias do Colo/complicações , Neoplasias do Colo/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Hipóxia/complicações , Hipóxia/genética , Oxirredução
10.
J Immunol ; 197(6): 2250-60, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27521345

RESUMO

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.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Células Precursoras de Linfócitos B/fisiologia , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Animais , Proliferação de Células , Sobrevivência Celular , Glicólise/efeitos dos fármacos , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Fosforilação/efeitos dos fármacos , Células Precursoras de Linfócitos B/efeitos dos fármacos , Células Precursoras de Linfócitos B/imunologia , Células Precursoras de Linfócitos B/metabolismo , Proteína Regulatória Associada a mTOR , Transdução de Sinais , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/deficiência , Fatores de Transcrição , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
11.
Chemistry ; 23(67): 16966-16971, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29077239

RESUMO

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).


Assuntos
Antineoplásicos/farmacologia , Antígenos CD13/metabolismo , Doxorrubicina/farmacologia , Nanocápsulas/química , Peptídeos Cíclicos/química , Dióxido de Silício/química , Antineoplásicos/química , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular , Preparações de Ação Retardada , Doxorrubicina/química , Liberação Controlada de Fármacos , Glutationa/química , Humanos , Conformação Molecular , Oligopeptídeos/química , Tamanho da Partícula , Porosidade , Propriedades de Superfície
12.
Proc Natl Acad Sci U S A ; 111(19): 7066-71, 2014 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-24785297

RESUMO

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.


Assuntos
Proteínas de Transporte/imunologia , Proteínas de Transporte/metabolismo , Metabolismo Energético/imunologia , Células T Matadoras Naturais/imunologia , Células T Matadoras Naturais/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Síndrome de Birt-Hogg-Dubé/imunologia , Síndrome de Birt-Hogg-Dubé/metabolismo , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Proteínas de Transporte/genética , Sobrevivência Celular/imunologia , Feminino , Homeostase/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células T Matadoras Naturais/citologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Serina-Treonina Quinases TOR/imunologia , Serina-Treonina Quinases TOR/metabolismo , Timo/citologia , Timo/imunologia
13.
Anal Chem ; 88(6): 3333-40, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26872241

RESUMO

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.


Assuntos
Metais Pesados/análise , Peptídeos/química , Fluorescência , Concentração de Íons de Hidrogênio , Limite de Detecção , Soluções , Espectrometria de Fluorescência , Água
14.
Nanomedicine ; 12(5): 1219-29, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26945975

RESUMO

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.


Assuntos
Nanopartículas , Fármacos Neuroprotetores/administração & dosagem , RNA Interferente Pequeno/administração & dosagem , Administração Intranasal , Animais , Encéfalo , Gelatina , Infarto da Artéria Cerebral Média/tratamento farmacológico , Ratos
15.
Xenotransplantation ; 22(4): 249-59, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26174875

RESUMO

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.


Assuntos
Hepatócitos/transplante , Falência Hepática Aguda/terapia , Transplante Heterólogo/métodos , Acetaminofen/toxicidade , Albuminas/biossíntese , Animais , Animais Recém-Nascidos , Agregação Celular , Sobrevivência Celular , Células Cultivadas , Modelos Animais de Doenças , Sobrevivência de Enxerto , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , Falência Hepática Aguda/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Esferoides Celulares/transplante , Sus scrofa , Suínos , Porco Miniatura , Ureia/metabolismo
16.
Ann Otol Rhinol Laryngol ; 124(1): 62-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25048959

RESUMO

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.


Assuntos
Etanol/administração & dosagem , Escleroterapia/métodos , Solventes/administração & dosagem , Cisto Tireoglosso/terapia , Adolescente , Adulto , Estudos de Coortes , Feminino , Humanos , Injeções Intralesionais , Masculino , Pessoa de Meia-Idade , Cisto Tireoglosso/patologia , Resultado do Tratamento , Adulto Jovem
17.
J Korean Med Sci ; 30(7): 991-4, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26130966

RESUMO

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.


Assuntos
Diabetes Mellitus Tipo 1/cirurgia , Hipoglicemia/cirurgia , Transplante das Ilhotas Pancreáticas/métodos , Ilhotas Pancreáticas/cirurgia , Glicemia/análise , Feminino , Humanos , Terapia de Imunossupressão/métodos , Imunossupressores/uso terapêutico , Ilhotas Pancreáticas/fisiologia , Pessoa de Meia-Idade , República da Coreia , Doadores de Tecidos
18.
J Craniofac Surg ; 26(8): 2357-63, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26594968

RESUMO

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.


Assuntos
Má Oclusão Classe III de Angle/cirurgia , Mandíbula/cirurgia , Maxila/cirurgia , Cirurgia Ortognática/métodos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Adolescente , Adulto , Cefalometria , Feminino , Humanos , Masculino , Osteotomia de Le Fort , Recidiva , Reoperação , Adulto Jovem
19.
J Craniofac Surg ; 26(4): 1159-62, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26080148

RESUMO

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.


Assuntos
Enxerto de Osso Alveolar/métodos , Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Tomada de Decisões , Cirurgia Ortognática/métodos , Osteogênese por Distração/métodos , Adolescente , Cefalometria , Criança , Fenda Labial/diagnóstico , Fissura Palatina/diagnóstico , Humanos , Masculino , Prognóstico
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