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1.
Small ; 17(30): e2101185, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34145958

RESUMO

Two-photon supramolecular assembly with near-infrared (NIR) fluorescence emission is constructed from tetraphenylethene derivative possessing methoxyl and vinyl pyridine salt (TPE-2SP), cucurbit[8]uril (CB[8]), and ß-cyclodextrin modified hyaluronic acid (HA-CD). The obtained experimental results indicate that the TPE-2SP exhibits a very weak fluorescence emission at 650 nm, and then complexes with cucurbit[7]uril (CB[7]) to form 1:2 supramolecular pseudorotaxane with an enhanced NIR fluorescence emission at 660 nm. Compared with CB[7], CB[8] can assemble with TPE-2SP to be two-axial netlike pseudopolyrotaxane, resulting in close packing to increase TPE-2SP fluorescence emission with a redshift of 30 nm. Interestingly, TPE-2SP/CB[8] continues to assemble with cancer cell targeting agent HA-CD into nanoparticles, leading to assembling-induced further enhancement of NIR emission. Surprisingly, supramolecular nanoparticles have the two-photon character, and are successfully applied to mitochondrial targeting imaging. This supramolecular assembly system, with two-photon absorption and assembly-induced enhanced NIR luminescence properties, opens new way for biological targeted imaging.


Assuntos
Nanopartículas , Humanos , Ácido Hialurônico , Luminescência , Mitocôndrias , Polímeros
2.
Environ Sci Pollut Res Int ; 30(25): 67758-67770, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37115443

RESUMO

Endocrine-disrupting compounds (EDCs) are increasingly polluting water, making it of practical value to develop novel desirable adsorbents for removing these pollutants from wastewater. Here, a simple cross-linking strategy combined with gentle chemical activation was demonstrated to prepare starch polyurethane-activated carbon (STPU-AC) for adsorbing BPA in water. The adsorbents were characterized by various techniques such as FTIR, XPS, Raman, BET, SEM, and zeta potential, and their adsorption properties were investigated comprehensively. Results show that STPU-AC possesses a large surface area (1862.55 m2·g-1) and an abundance of functional groups, which exhibited superior adsorption capacity for BPA (543.4 mg·g-1) and favorable regenerative abilities. The adsorption of BPA by STPU-AC follows a pseudo-second-order kinetic model and a Freundlich isotherm model. The effect of aqueous solution chemistry (pH and ionic strength) and the presence of other contaminants (phenol, heavy metals, and dyes) on BPA adsorption was also analyzed. Moreover, theoretical studies further demonstrate that hydroxyl oxygen and pyrrole nitrogen are the primary adsorption sites. We found that the efficient recovery of BPA was associated with pore filling, hydrogen-bonding interaction, hydrophobic effects, and π-π stacking. These findings demonstrate the promising practical application of STPU-AC and provide a basis for the rational design of starch-derived porous carbon.


Assuntos
Carvão Vegetal , Poluentes Químicos da Água , Carvão Vegetal/química , Poliuretanos , Amido , Poluentes Químicos da Água/análise , Fenóis/química , Água , Compostos Benzidrílicos/química , Adsorção , Cinética , Concentração de Íons de Hidrogênio
3.
Int J Biol Macromol ; 193(Pt A): 71-80, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34637817

RESUMO

Herein, a TEMPO-oxidized cellulose-grafted-polystyrene hypercrosslinked polymer (TOC-PS-HCP) was synthesized facilely by TEMPO oxidation, grafting copolymerization and post crosslinking route. Based on the structural characterization, it was confirmed that TOC-PS-HCP mainly consisted of polystyrene chain on cellulose and rigid crosslinked bridge. Additionally, the as-prepared TOC-PS-HCP displayed appropriate hydrophobicity (water contact angle = 102.44°) and high specific surface area (SBET = 601.20 m2·g--1), which could efficiently recover ethylbenzene and styrene from PO/SM wastewater. The adsorption experiment was conducted to study the recovery performance for ethylbenzene and styrene in the aqueous phase. The results showed that TOC-PS-HCP could recover ethylbenzene and styrene quickly by adsorption process, and maintain a stable recovery rate both in different aqueous conditions and recycle experiments. The adsorption experiment in the simulated wastewater solution showed that TOC-PS-HCP exhibited the greater affinity for ethylbenzene and styrene than other substrates. Furthermore, a possible mechanism for the efficient recovery of ethylbenzene and styrene was suggested on the basis of experimental and theoretical results, which may be associated with van der Waals force and π-π stacking.


Assuntos
Celulose/química , Óxidos N-Cíclicos/química , Polímeros/química , Águas Residuárias/química , Purificação da Água/métodos , Adsorção
4.
J Craniofac Surg ; 20(6): 2013-9, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19881378

RESUMO

OBJECTIVES: To analyze variants of the craniofacial phenotypes in children with velocardiofacial syndrome (VCFS) and children with cleft palates with a new protocol of landmarks using a three-dimensional computed tomography (CT)-reconstructed model in a cross-sectional group experimental design. MATERIALS AND METHODS: We present a retrospectively reviewed case series of 21 patients with VCFS, verified by short-tandem repeat techniques, and 20 children with cleft palate with age- and sex-matched controls from the Craniofacial Cleft Department of Oral and Maxillofacial Surgery of the 9th Shanghai People's Hospital. The records during the period between January 2005 and December 2008 were analyzed. The sample population of 41 children in this study was scanned with spiral CT. These images were reconstructed into three-dimensional models by SimPlant 11.2 and were analyzed with a new protocol of landmarks to test the variants of craniofacial phenotypes. RESULTS: All of the children with VCFS demonstrated velopharyngeal incompetence and craniofacial deformities. Measurements in the standard coordinate system demonstrated significant shorter cranial base, cervical vertebrae, longer maxilla height, and palatal angle. For the velopharyngeal variants, greater depth but lesser width of the pharyngeal cavity was shown in the VCFS group. CONCLUSIONS: Three-dimensional CT can provide precise data on craniofacial variants in children with distinctive morphologic features of VCFS.


Assuntos
Cromossomos Humanos Par 22/genética , Síndrome de DiGeorge/diagnóstico por imagem , Síndrome de DiGeorge/genética , Radiografia Dentária Digital/estatística & dados numéricos , Adolescente , Estudos de Casos e Controles , Cefalometria , Criança , Estudos Transversais , Síndrome de DiGeorge/complicações , Feminino , Humanos , Imageamento Tridimensional/métodos , Masculino , Palato Duro/diagnóstico por imagem , Palato Duro/patologia , Fenótipo , Estudos Retrospectivos , Deleção de Sequência , Tomografia Computadorizada Espiral/estatística & dados numéricos , Insuficiência Velofaríngea/diagnóstico por imagem , Insuficiência Velofaríngea/etiologia , Insuficiência Velofaríngea/genética , Dimensão Vertical
5.
Oncotarget ; 7(2): 1796-807, 2016 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-26625202

RESUMO

Here, we report a novel non-epigenetic function of histone deacetylase (HDAC) 8 in activating cancer stem cell (CSC)-like properties in breast cancer cells by enhancing the stability of Notch1 protein. The pan-HDAC inhibitors AR-42 and SAHA, and the class I HDAC inhibitor depsipeptide, suppressed mammosphere formation and other CSC markers by reducing Notch1 expression in MDA-MB-231 and SUM-159 cells. Interrogation of individual class I isoforms (HDAC1-3 and 8) using si/shRNA-mediated knockdown, ectopic expression and/or pharmacological inhibition revealed HDAC8 to be the primary mediator of this drug effect. This suppression of Notch1 in response to HDAC8 inhibition was abrogated by the proteasome inhibitor MG132 and siRNA-induced silencing of Fbwx7, indicating Notch1 suppression occurred through proteasomal degradation. However, co-immunoprecipitation analysis indicated that HDAC8 did not form complexes with Notch1 and HDAC inhibition had no effect on Notch1 acetylation. In a xenograft tumor model, the tumorigenicity of breast cancer cells was decreased by HDAC8 knockdown. These findings suggest the therapeutic potential of HDAC8 inhibition to suppress Notch1 signaling in breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Histona Desacetilases/metabolismo , Células-Tronco Neoplásicas/metabolismo , Receptor Notch1/metabolismo , Proteínas Repressoras/metabolismo , Animais , Western Blotting , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Depsipeptídeos/farmacologia , Epigênese Genética , Feminino , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/genética , Humanos , Células MCF-7 , Camundongos Endogâmicos NOD , Camundongos SCID , Microscopia Confocal , Células-Tronco Neoplásicas/efeitos dos fármacos , Nylons/farmacologia , Fenilbutiratos/farmacologia , Estabilidade Proteica , Pirróis/farmacologia , Interferência de RNA , Receptor Notch1/genética , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/metabolismo , Transplante Heterólogo
6.
J Leukoc Biol ; 76(1): 135-44, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15107456

RESUMO

Interleukin (IL)-17 is the founding member of an emerging family of inflammatory cytokines whose functions remain poorly defined. IL-17 has been linked to the pathogenesis of rheumatoid arthritis, and numerous studies implicate this cytokine in inflammation-induced bone loss. It is clear that a major function of IL-17 is to amplify the immune response by triggering production of chemokines, cytokines, and cell-surface markers, ultimately leading to neutrophil chemotaxis and inflammation. As an IL-17 signaling deficiency in mice causes a dramatic reduction in neutrophil chemotaxis and a consequent increased susceptibility to bacterial infection, it is important to define gene targets involved in IL-17-mediated neutrophil trafficking. Here, we demonstrate that IL-17 and tumor necrosis factor alpha (TNF-alpha) cooperatively induce the lipopolysaccharide-inducible CXC chemokine (LIX; a.k.a., CXC chemokine ligand 5, Scya5, or murine granulocyte chemotactic protein-2) in the preosteoblast cell line MC3T3. LIX is induced rapidly at the mRNA and protein levels, likely through the activation of new gene transcription. Conditioned media from MC3T3 cells treated with IL-17 and/or TNF-alpha stimulates neutrophil mobility potently, and LIX is a significant contributing factor to this process. In addition, IL-17 cooperates with bacterial components involved in periodontal disease to up-regulate LIX expression. This study is the first demonstration of LIX expression in bone cells and has implications for inflammatory bone diseases such as arthritis and periodontal disease.


Assuntos
Quimiocinas CXC/biossíntese , Inflamação/imunologia , Interleucina-17/imunologia , Infiltração de Neutrófilos/imunologia , Osteoblastos/imunologia , Animais , Artrite/imunologia , Northern Blotting , Movimento Celular/efeitos dos fármacos , Movimento Celular/imunologia , Células Cultivadas , Quimiocina CXCL5 , Meios de Cultivo Condicionados/farmacologia , Ensaio de Imunoadsorção Enzimática , Regulação da Expressão Gênica , Interleucina-17/farmacologia , Camundongos , Infiltração de Neutrófilos/efeitos dos fármacos , Análise de Sequência com Séries de Oligonucleotídeos , Osteoblastos/efeitos dos fármacos , Doenças Periodontais/imunologia , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/farmacologia
7.
Bioresour Technol ; 177: 159-68, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25485736

RESUMO

Bagasse liquefaction (BL) in water, tetralin, and water/tetralin mixed solvents (WTMS) was investigated, and effects of tetralin content in WTMS, temperature, and alkaline pretreatment of bagasse on liquefaction efficiency were studied. At 300°C, bagasse conversion in WTMS with tetralin content higher than 50 wt% was 86-87 wt%, whereas bagasse conversion in water or tetralin was 67 wt% or 84 wt%, respectively. Because the solid conversion from liquefaction in WTMS with tetralin content higher than 50 wt% was always higher than that in water or tetralin at temperatures between 250 and 300°C, a synergic effect between water and tetralin is suggested. Alkaline pretreatment of bagasse resulted in significantly higher conversion and heavy oil yield from BL in water or WTMS. The effect of deoxygenation by the present liquefaction method is demonstrated by lower oxygen contents (16.01-19.59 wt%) and higher heating values (31.9-34.8 MJ/kg) in the produced oils.


Assuntos
Álcalis/farmacologia , Biotecnologia/métodos , Celulose/química , Tetra-Hidronaftalenos/farmacologia , Água/farmacologia , Análise Diferencial Térmica , Cromatografia Gasosa-Espectrometria de Massas , Óleos/química , Hidróxido de Sódio/farmacologia , Solventes , Temperatura , Termogravimetria
8.
Atherosclerosis ; 241(2): 657-63, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26117403

RESUMO

OBJECTIVE: Bisphenol A (BPA) is a chemical produced at high volumes and used widely in food and drink packaging. In adults, elevated BPA concentrations are associated with cardiovascular disease. BPA exposure is plausibly linked to atherosclerosis in adolescents and young adults, but evidence is lacking to date. METHODS: We recruited 886 subjects (12-30 years of age) from a population-based sample of adolescents and young adults based on a mass urine screening to determine the relationship between serum levels of BPA and carotid intima-media thickness (CIMT). RESULTS: The geometric mean (standard deviation) of concentrations of BPA were 1.72 (5.5) ng/mL After controlling for confounding factors, linear regression analyzes showed a 1-unit increase in natural log BPA was significantly associated with an increase in mean CIMT (mm) (ß = 0.005, 95% C.I. = 0.003-0.007, p < 0.001) and other measurement of CIMT (including right and left side of common carotid artery, carotid bulb and internal carotid artery). CONCLUSION: Higher serum concentrations of BPA were associated with increased CIMT in this cross-sectional study of adolescents and young adults. Studies to clarify the mechanisms of these associations are needed.


Assuntos
Compostos Benzidrílicos/sangue , Espessura Intima-Media Carotídea , Fenóis/sangue , Adolescente , Adulto , Aterosclerose/etiologia , Compostos Benzidrílicos/urina , Artérias Carótidas/efeitos dos fármacos , Artérias Carótidas/patologia , Criança , Estudos Transversais , Feminino , Humanos , Modelos Lineares , Masculino , Fenóis/urina , Plásticos , Fatores de Risco , Adulto Jovem
9.
Int J Cardiol ; 174(3): 688-95, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24820736

RESUMO

BACKGROUND: Biodegradable polymers have been applied as bulk or coating materials for coronary artery stents. The degradation of polymers, however, could induce endothelial dysfunction and aggravate neointimal formation. Here we use polymeric microparticles to simulate and demonstrate the effects of degraded stent materials on phagocytic activity, cell death and dysfunction of macrophages and endothelial cells. METHODS: Microparticles made of low molecular weight polyesters were incubated with human macrophages and coronary artery endothelial cells (ECs). Microparticle-induced phagocytosis, cytotoxicity, apoptosis, cytokine release and surface marker expression were determined by immunostaining or ELISA. Elastase expression was analyzed by ELISA and the elastase-mediated polymer degradation was assessed by mass spectrometry. RESULTS: We demonstrated that poly(D,L-lactic acid) (PLLA) and polycaprolactone (PCL) microparticles induced cytotoxicity in macrophages and ECs, partially through cell apoptosis. The particle treatment alleviated EC phagocytosis, as opposed to macrophages, but enhanced the expression of vascular cell adhesion molecule (VCAM)-1 along with decreased nitric oxide production, indicating that ECs were activated and lost their capacity to maintain homeostasis. The activation of both cell types induced the release of elastase or elastase-like protease, which further accelerated polymer degradation. CONCLUSIONS: This study revealed that low molecule weight PLLA and PCL microparticles increased cytotoxicity and dysregulated endothelial cell function, which in turn enhanced elastase release and polymer degradation. These indicate that polymer or polymer-coated stents impose a risk of endothelial dysfunction after deployment which can potentially lead to delayed endothelialization, neointimal hyperplasia and late thrombosis.


Assuntos
Vasos Coronários/patologia , Células Endoteliais/fisiologia , Macrófagos/fisiologia , Polímeros/administração & dosagem , Stents , Contagem de Células/métodos , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Células Cultivadas , Vasos Coronários/citologia , Vasos Coronários/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Humanos , Macrófagos/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Fagocitose/fisiologia , Polímeros/efeitos adversos , Stents/efeitos adversos
10.
Artigo em Inglês | MEDLINE | ID: mdl-11936767

RESUMO

Apolipoprotein H (ApoH) is a plasma glycoprotein isolated from human serum. It plays a key role in the interaction with lipids. For the first time, the concentration of ApoH adsorbed on the lipid monolayer has been determined, and was done so using capillary electrophoresis. Based on this determination, an interaction model of ApoH and lipid monolayer was constructed, and this interaction is one of nonspecific adsorption. A neutral coated capillary (50 cm x 100 microm i.d.) and a negative voltage of 15 kV were used to separate ApoH. The calibration curve of ApoH was built using a detection limit of 50 microg/mL(-1) (near to 1 microM), and the RSD of the relative migration time of ApoH was 1.4% (n = 7).


Assuntos
Glicoproteínas/sangue , Lipossomos/química , Adsorção , Eletroforese Capilar/métodos , Glicoproteínas/química , Glicoproteínas/isolamento & purificação , Humanos , Dodecilsulfato de Sódio , beta 2-Glicoproteína I
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