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1.
Langmuir ; 38(40): 12307-12315, 2022 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-36154182

RESUMEN

Chemodynamic therapy (CDT) is a promising hydroxyl radical (•OH)-mediated tumor therapeutic method with desirable tumor specificity and minimal side effects. However, the efficiency of CDT is restricted by the pH condition, insufficient H2O2 level, and overexpressed reductive glutathione (GSH), making it challenging to solve these problems simultaneously to improve the efficacy of CDT. Herein, a kind of polyvinylpyrrolidone-stabilized, sorafenib-loaded copper peroxide (CuO2-PVP-SRF) nanoparticle (NPs) was designed and developed for enhanced CDT against tumor cells through the synergetic pH-independent Fenton-like, H2O2 self-supplying, and GSH depletion strategy. The prepared CuO2-PVP-SRF NPs can be uptaken by 4T1 cells to specifically release Cu2+, H2O2, and SRF under acidic conditions. The intracellular GSH can be depleted by SRF-induced system xc- dysfunction and Cu2+-participated redox reaction, causing the inactivation of GPX4 and generating Cu+. A great amount of •OH was produced in this reducing capacity-disrupted condition by the Cu+-mediated Fenton-like reaction, causing cell apoptosis and lipid hydroperoxide accumulation-induced ferroptosis. They display an excellent 4T1 cell killing outcome through the improved •OH production capacity. The CuO2-PVP-SRF NPs display elevated therapeutic efficiency of CDT and show good promise in further tumor treatment applications.


Asunto(s)
Nanopartículas , Neoplasias , Línea Celular Tumoral , Cobre/farmacología , Glutatión , Humanos , Peróxido de Hidrógeno , Radical Hidroxilo , Peróxidos Lipídicos/farmacología , Neoplasias/tratamiento farmacológico , Oxidación-Reducción , Peróxidos/farmacología , Peróxidos/uso terapéutico , Povidona , Sorafenib/farmacología , Microambiente Tumoral
2.
Biomacromolecules ; 20(7): 2809-2820, 2019 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-31185717

RESUMEN

Transient increase of reactive oxygen species (ROS) is vital for some physiological processes, whereas the chronic and sustained high ROS level is usually implicated in the inflammatory diseases and cancers. Herein, we report the innovative redox-responsive theranostic micellar nanoparticles that are able to load anticancer drugs through coordination and hydrophobic interaction and to fluorescently monitor the intracellular redox status. The nanoparticles were formed by the amphiphilic block copolymers composed of a PEG segment and a selenide-containing hydrophobic polycarbonate block with a small fraction of coumarin-based chromophore. Under the alternative redox stimulation that might be encountered in the physiological process of some healthy cells, these nanoparticles underwent the reversible changes in size, morphology, and fluorescence intensity. With the assistance of small model compounds, we clarified the chemistry behind these changes, that is, the redox triggered reversible transformation between selenide and selenoxide. Upon the monotonic oxidation similar to the sustained high ROS level of cancer cells, the nanoparticles could be disrupted completely, which was accompanied by the drastic decrease in fluorescence. Cisplatin and paclitaxel were simultaneously coloaded in the nanoparticles with a moderate efficacy, and the coordination between selenide and platinum improved the stability of the drug-loaded nanoparticles against dilution. The naked nanoparticles are cytocompatible, whereas the dual drug-loaded nanoparticles exhibited a concentration dependent and synergistic cytotoxicity to triple-negative breast cancer (TNBC) cells. Of importance, the drug-loaded nanoparticles are much more toxic to TNBC cells than to normal cells due in part to ROS overproduction in the former cell lines.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Sistemas de Liberación de Medicamentos , Nanopartículas/química , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Doxorrubicina/farmacología , Liberación de Fármacos , Colorantes Fluorescentes/química , Colorantes Fluorescentes/farmacología , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Ratones , Micelas , Oxidación-Reducción , Paclitaxel/química , Paclitaxel/farmacología , Cemento de Policarboxilato/química , Cemento de Policarboxilato/farmacología , Especies Reactivas de Oxígeno/química , Neoplasias de la Mama Triple Negativas/patología
3.
Environ Sci Technol ; 47(3): 1598-605, 2013 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-23323771

RESUMEN

A binary system consisting of polyethylene glycol (PEG, proton donor)/PEG-functionalized base with suitable basicity was developed for efficient gas desulfurization (GDS) and can be regarded as an alternative approach to circumvent the energy penalty problem in the GDS process. High capacity for SO(2) capture up to 4.88 mol of SO(2)/mol of base was achieved even under low partial pressure of SO(2). Furthermore, SO(2) desorption runs smoothly under mild conditions (N(2), 25 °C) and no significant drop in SO(2) absorption was observed after five-successive absorption-desorption cycles. On the other hand, the absorbed SO(2) by PEG(150)MeIm/PEG(150), being considered as the activated form of SO(2), can be directly transformed into value-added chemicals under mild conditions, thus eliminating the energy penalty for SO(2) desorption and simultaneously realizing recycle of the absorbents. Thus, this SO(2) capture and utilization (SCU) process offers an alternative way for GDS and potentially enables the SO(2) conversion from flue gas to useful chemicals as a value-added process.


Asunto(s)
Álcalis/química , Polietilenglicoles/química , Dióxido de Azufre/aislamiento & purificación , Absorción , Dióxido de Carbono/análisis , Compuestos Epoxi/análisis , Compuestos Epoxi/química , Imidazoles/química , Peso Molecular , Presión Parcial , Protones , Reciclaje , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura
4.
Nano Lett ; 12(3): 1486-90, 2012 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-22316380

RESUMEN

We report a direct observation of surface dominated conduction in an intrinsic Bi(2)Se(3) thin film with a thickness of six quintuple layers grown on lattice-matched CdS (0001) substrates by molecular beam epitaxy. Shubnikov-de Haas oscillations from the topological surface states suggest that the Fermi level falls inside the bulk band gap and is 53 ± 5 meV above the Dirac point, which is in agreement with 70 ± 20 meV obtained from scanning tunneling spectroscopies. Our results demonstrate a great potential of producing genuine topological insulator devices using Dirac Fermions of the surface states, when the film thickness is pushed to nanometer range.


Asunto(s)
Bismuto/química , Membranas Artificiales , Nanoestructuras/química , Nanoestructuras/ultraestructura , Selenio/química , Conductividad Eléctrica , Ensayo de Materiales , Tamaño de la Partícula , Propiedades de Superficie
5.
Nano Lett ; 12(3): 1170-5, 2012 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-22313251

RESUMEN

Exploring exciting and exotic physics, scientists are pursuing practical device applications for topological insulators. The Dirac-like surface states in topological insulators are protected by the time-reversal symmetry, which naturally forbids backscattering events during the carrier transport process, and therefore offers promising applications in dissipationless spintronic devices. Although considerable efforts have been devoted to controlling their surface conduction, limited work has been focused on tuning surface states and bulk carriers in Bi(2)Te(3) nanostructures by external field. Here we report gate-tunable surface conduction in Na-doped Bi(2)Te(3) topological insulator nanoplates. Significantly, by applying external gate voltages, such topological insulators can be tuned from p-type to n-type. Our results render a promise in finding novel topological insulators with enhanced surface states.


Asunto(s)
Bismuto/química , Membranas Artificiales , Nanoestructuras/química , Nanoestructuras/ultraestructura , Semiconductores , Sodio/química , Telurio/química , Conductividad Eléctrica , Ensayo de Materiales , Tamaño de la Partícula , Propiedades de Superficie
6.
Environ Technol ; 44(5): 631-646, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34516358

RESUMEN

The adsorption of chlorinated aromatic compounds (CACs) on pristine biochar was often limited. Surface modification can greatly improve the adsorption capacity of biochar. In this work, by pyrolysis activation of rubber-seed shell wastes, nitrogen auto-doped biochar (RSS-NBC) was synthesized and used for purifying CACs-containing wastewater. Systematic characterization results showed that after proper treatment, the as-prepared RSS-NBC had high specific surface area, abundant surface oxygen- and nitrogen-containing functional groups, and nano-scale pore structure. Batch adsorption experiments were conducted with using three typical CACs probing pollutants, i.e. 1,2-dichlorobenzene (1,2-DCB), 2,4-dichlorophenol (2,4-DCP) and 2,4-dichlorobenzoic acid (2,4-DCBA). The adsorption experiments results showed that the maximum adsorption amounts of 1, 2-DCB, 2,4-DCP, and 2,4-DCBA could reach 2284, 1921, and 1142 mg/g at 298.15 K. Moreover, 90% of the equilibrium adsorption amount can be reached within 0.5 h. The adsorption kinetic results showed that the adsorption processes of the three CACs followed the pseudo-second-order rate model and were dominated by chemisorption. Also, the adsorption isotherms of 1, 2-DCB and 2, 4-DCP belonged to the Freundlich model and were valid for multilayer adsorption, while the adsorption of 2,4-DCBA followed Langmuir model and single-layer adsorption. The thermodynamics data indicated that the spontaneous adsorption process of 1, 2-DCB and 2, 4-DCP was endothermic while that of 2,4-DCBA was exothermic. After 5 cycles of adsorption-regeneration, the removal efficiency of RSS-NBC particles still remained more than 80% for the three typical CACs, indicating that it could be reused as an effective and retrievable adsorbent in the treatment of CACs-containing effluents.


Asunto(s)
Goma , Contaminantes Químicos del Agua , Adsorción , Pirólisis , Carbón Orgánico/química , Agua , Cinética
7.
J Colloid Interface Sci ; 639: 434-443, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36822043

RESUMEN

Mass cytometry (MC) is an emerging bioanalytical technique for high-dimensional biomarkers interrogation simultaneously on individual cells. However, the sensitivity and multiplexed analysis ability of MC was highly restricted by the current metal chelating polymer (MCP) mass tags. Herein, a new design strategy for MC mass tags by using a commercial available and low cost classical material, polystyrene nanoparticle (PS-NP) to carry metals was reported. Unlike inorganic materials, sub-micron-grade metal-loaded polystyrene can be easily detected by MC, thus it is not essential to pursue extremely small particle size in this mass tag design strategy. An altered cell staining buffer can significantly lower the nonspecific binding (NSB) of non-functionalized PS-NPs, revealing another method to lower NSB beside surface modification. The metal doped PS-NP_Abs mass tags showed high compatibility with MCP mass tags and 5-fold higher sensitivity. By using Hf doped PS-NP_Abs as mass tags, four new MC detection channels (177Hf, 178Hf, 179Hf and 180Hf) were developed. In general, this work provides a new strategy in designing MC mass tags and lowering NSB, opening up possibility of introducing more potential MC mass tag candidates.


Asunto(s)
Nanopartículas , Poliestirenos , Quelantes , Metales
8.
Int J Biol Macromol ; 237: 124121, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36966858

RESUMEN

A scheme combining alkali­oxygen cooking and ultrasonic etching cleaning was developed for the short range preparation of CNF from bagasse pith, which has a soft tissue structure and is rich in parenchyma cells. This scheme expands the utilization path of sugar waste sucrose pulp. The effect of NaOH, O2, macromolecular carbohydrates, and lignin on subsequent ultrasonic etching was analyzed, and it was found that the degree of alkali­oxygen cooking was positively correlated with the difficulty of subsequent ultrasonic etching. The mechanism of ultrasonic nano-crystallization was found to be the bidirectional etching mode from the edge and surface cracks of the cell fragments by ultrasonic microjet in the microtopography of CNF. The optimum preparation scheme was obtained under the condition of 28 % NaOH content and 0.5 MPa O2, which solves the problem of low-value utilization of bagasse pith and environmental pollution, providing a new possibility for the source of CNF.


Asunto(s)
Álcalis , Oxígeno , Oxígeno/química , Álcalis/química , Hidróxido de Sodio/química , Ultrasonido , Celulosa/química , Carbohidratos , Culinaria
9.
Environ Int ; 171: 107715, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36577297

RESUMEN

Tire wear particles (TWPs) enter road surface with the friction between tires and road surfaces. Under the volatilization, leaching, and transformation action on TWPs by sunlight and rain, tire additives are released into urban water systems, such as surface rainfall runoff, wastewater treatment plants (WWTPs), receiving surface waters, and drinking water treatment plant (DWTP). In this study, we investigated the occurrence of 23 tire additives and their transformation products in the urban water system of the Pearl River Delta region, South China. Nineteen target compounds were detected in the surface runoff, with 1,3-Diphenylguanidine (DPG) showing highest maximum concentration of 58780 ng/L. Benzothiazole and its transformation products are detected at the frequency of 100 % with the total concentrations of 480-42160 ng/L. The antioxidant derivative N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine-quinone (6PPD-Q) was also detected up to 1562 ng/L, which was considerably higher than that of the parent compound 6PPD (the maximum concentration of 7.52 ng/L). Eleven and 8 compounds were detected in WWTPs influents and effluents, respectively, with removal rates of - 62-100 %. Seventeen compounds were detected in the receiving Zhujiang and Dongjiang rivers, while 9 compounds were detected in drinking water sources and DWTP samples. Road runoff, with total concentrations of target compounds up to 79200 ng/L, is suggested as the main non-point source for receiving rivers, while WWTPs effluents are the point sources due to incomplete removal of target compounds after accepting the initial runoff. 6PPD-Q and other 10 compounds displayed median to high ecological risks in surface waters, and the human daily intake of tire additives was estimated to be 2.63 × 10-8-3.16 × 10-5 mg/(kg d) via drinking water. This is the first report of the 6PPD-Q and 1,3-Diphenylurea levels in surface waters in China.


Asunto(s)
Benzoquinonas , Carbanilidas , Agua Potable , Fenilendiaminas , Ríos , Contaminantes Químicos del Agua , Humanos , China , Agua Potable/análisis , Agua Potable/química , Monitoreo del Ambiente , Ríos/química , Contaminantes Químicos del Agua/análisis , Guanidinas/análisis , Goma/química , Fenilendiaminas/análisis , Benzoquinonas/análisis , Carbanilidas/análisis
10.
Phys Chem Chem Phys ; 14(45): 15832-9, 2012 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-23090138

RESUMEN

Up to now, flue-gas desulfurization (FGD) is one of the most effective techniques to control SO(2) emission from the combustion of fossil fuels. The conventional technology for FGD poses serious inherent drawbacks such as formation of byproducts and volatilization of solvents. In this work, polyethylene glycol (PEG)-functionalized Lewis basic ionic liquids (ILs) derived from DABCO were proved to be highly efficient absorbents for FGD due to its specific features such as high thermal stability, negligible vapor pressure, high loading capacity. Notably, PEG(150)MeDABCONTf(2) gave an extremely high SO(2) capacity (4.38 mol mol(-1) IL), even under 0.1 bar SO(2) partial pressure (1.01 mol mol(-1) IL), presumably owing to the strong SO(2)-philic characterization of the PEG chain. Furthermore, the absorbed SO(2) could be easy to release by just bubbling N(2) at room temperature, greatly reducing energy requirement for SO(2) desorption. In addition, SO(2)/CO(2) selectivity (110) of PEG(150)MeDABCONTf(2) is two times larger than the non-functionalized imidazolium IL (45). On the other hand, through activation of SO(2) with the tertiary nitrogen in the cation, Lewis basic ILs such as PEG(150)MeDABCOBr proved to be efficient catalysts for the conversion of SO(2) to some value-added chemicals such as cyclic sulfites without utilization of any organic solvent or additive. Thus, this protocol would pave the way for the development of technological innovation towards efficient and low energy demanded practical process for SO(2) absorption and subsequent transformation.


Asunto(s)
Líquidos Iónicos/química , Polietilenglicoles/química , Dióxido de Azufre/química , Estructura Molecular , Sulfitos/síntesis química , Sulfitos/química
11.
ChemSusChem ; 15(23): e202201455, 2022 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-36163546

RESUMEN

Immobilizing cobalt phthalocyanine (CoPc) onto the electrode surface is a significant approach to performing efficient electrochemical CO2 reduction reaction (ECO2 RR). Herein, sulfylphenoxy decorated CoPc cross-linked polypyrrole is prepared by in situ polymerization on the surface of carbon cloth. The synthesized N-rich catalyst exhibits above 95 % Faradaic efficiency toward CO (FECO ) at -0.9 V versus reversible hydrogen electrode (RHE) at least for 10 h in aqueous solution and even enables direct electrolysis at low CO2 concentrations, being potential for coupling ECO2 RR with CO2 capture. This facile in situ polymerization strategy would pave the way for developing efficient and practical electrocatalysis for ECO2 RR.


Asunto(s)
Polímeros , Pirroles , Dióxido de Carbono , Indoles
12.
Bioresour Technol ; 319: 124162, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32992273

RESUMEN

Napier grass is a promising energy source on account of its strong adaptability and high productivity. Herein, an O2-aided alkaline pretreatment with mild operating conditions was developed to modify Napier grass stem structure for improving its fractionated efficiency and enzymatic digestibility. Compared with the conventional alkaline pretreatment, it could be proceeded at lower temperature (80 °C) and dilute NaOH solution (1%) to remove over 80% lignin and retain 92% cellulose. The recovered lignin possessed typical structures of native lignin and well-preserved molecular weight, anticipating feasible potential in preparation of biomaterials or aromatic chemicals. Coupled with the enzymatic hydrolysis managements of solid remain and hydrolysate after the pretreatment, the recovery yields of glucose and xylose based on the raw material feeds reached 89.7% and 90.2%, respectively. This contribution demonstrates a highly-reliable strategy to fractionate Napier grass stem for maximizing fermentation sugar production and valorizing lignin toward sustainable biorefinery processes.


Asunto(s)
Lignina , Pennisetum , Celulosa , Hidrólisis , Xilosa
13.
Carbohydr Polym ; 263: 117981, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33858576

RESUMEN

The existence of hydroxyl and carboxyl groups makes the photothermal stability of cellulose nanofibers (CNFs) poor and thus limits its scale application. This problem could be solved by doping layered double hydroxides (LDHs) nanopowders with opposite charge on the surface of CNFs. This work mainly focused on investigation of the influence of the crystal morphology of the inorganic ultraviolet shielding agent (i.e. ZnAl-LDHs) on the thermal stability of CNFs/ZnAl-LDHs composited films. The results showed that the morphology of LDHs was positively correlated with the photothermal stability of CNFs-based films. Specially, the ZnAl-LDHs with uniform crystal morphology could be prepared by controlling the molar ratio of Zn/Al at 3:1 and thus enhance the photothermal stability of CNFs-based films without any serious light transmittance deteriorating after doping. This work provided a practical and effective way for preparation of photothermal-stable CNFs-based transparent films for industrial application in the fields of photonics and electronics.


Asunto(s)
Aluminio/química , Celulosa/química , Hidróxidos/química , Nanofibras/química , Compuestos de Zinc/química , Adsorción , Cristalización , Electrónica , Luz , Óptica y Fotónica , Temperatura
14.
Sci Rep ; 11(1): 16929, 2021 08 19.
Artículo en Inglés | MEDLINE | ID: mdl-34413406

RESUMEN

Patients receiving lipid emulsions are at increased risk of contracting catheter-related bloodstream infections (CRBSIs) in the clinic. More than 15% of CRBSIs are polymicrobial. The objective of this study was to explore the effects of lipid emulsions on the formation of Escherichia coli (E. coli)-Candida albicans (C. albicans) mixed-species biofilms (BFs) on polyvinyl chloride (PVC) surfaces and the underlying mechanism. Mixed-species BFs were produced by coculturing E. coli and C. albicans with PVC in various concentrations of lipid emulsions. Crystal violet staining and XTT assays were performed to test the mixed-species BF biomass and the viability of microbes in the BFs. The microstructures of the BFs were observed by an approach that combined confocal laser scanning microscopy, fluorescence in situ hybridization, and scanning electron microscopy. The study found that lipid emulsions could promote the formation of E. coli-C. albicans mixed-species BFs, especially with 10% lipid emulsions. The mechanism by which lipid emulsions promote mixed-species BF formation may involve significant upregulation of the expression of the flhDC, iha, HTA1, and HWP1 genes, which are associated with bacterial motility, adhesion, and BF formation. The results derived from this study necessitate strict aseptic precautions when handling lipid emulsions and avoiding the use of high concentrations of lipid emulsions for as long as possible.


Asunto(s)
Biopelículas , Candida albicans , Emulsiones/farmacología , Escherichia coli , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Candida albicans/efectos de los fármacos , Candida albicans/patogenicidad , Escherichia coli/efectos de los fármacos , Escherichia coli/patogenicidad , Cloruro de Polivinilo/química
15.
Peptides ; 130: 170333, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32497565

RESUMEN

The cardioprotective effect of oxytocin (OT) has been well established. However, there are no related studies on the role of endothelia in oxytocin-induced cardioprotection. Endothelial dysfunction (ED) model was established by injection of 0.01 % Triton X-100 in the isolated rat heart. Oxytocin pretreatment was conducted at the end of stabilization for 40 min, followed by 30 min global ischemia and 60 min reperfusion to induce I/R injury. Coronary perfusion pressure, hemodynamics and arrhythmia severity scores were measured respectively. High-sensitivity cardiac troponin T (hs-cTnT) was evaluated by enzyme-linked immunosorbent assay. Infarct size was detected by triphenyltetrazolium chloride staining. The morphological changes in coronary endothelium were observed by scanning electron microscopy. Injection of 0.01 % Triton X-100 caused significant reduction of CPP induced by histamine and endothelium removal from scanning electron microscopy, but SNP had no significant effect. Oxytocin pretreatment showed significant recovery in LVDP, ±dp/dtmax, RPP and SI after reperfusion (P <  0.05). Additionally, I/R injury led to a rise of arrhythmia severity score, hs-cTnT and infarct size. No significant differences between ED-OT-I/R and OT-I/R groups were found in arrhythmia severity score, hs-cTnT, and infarct size (P >  0.05). I/R injury exacerbated the decrease in CPP and worsened the migration, deformation, and fracture of coronary endothelium, while oxytocin reversed these injuries. Despite the presence of endothelial damages, oxytocin partially alleviated I/R- and Triton-induced endothelial damages. The cardioprotective effects of oxytocin are independent of endothelial function in alleviating I/R injury and I/R-induced coronary endothelial dysfunction.


Asunto(s)
Cardiotónicos/farmacología , Endotelio Vascular/efectos de los fármacos , Daño por Reperfusión Miocárdica/prevención & control , Oxitocina/farmacología , Animales , Vasos Coronarios/fisiopatología , Endotelio Vascular/fisiopatología , Corazón/efectos de los fármacos , Hemodinámica/efectos de los fármacos , Masculino , Miocardio/patología , Octoxinol/toxicidad , Técnicas de Cultivo de Órganos , Ratas Sprague-Dawley
16.
Nanoscale ; 10(47): 22252-22262, 2018 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-30465053

RESUMEN

Nano-drug delivery systems with multi-modality imaging capacities are worth pursuing because they integrate diagnostic and therapeutic functions. Herein, we report the design, synthesis and evaluation of modified iridium sulfide (IrSx) nanoparticles (NPs) for cancer therapy in vitro and in vivo. This nanosystem was prepared by modifying IrSx with polyethylene glycol (PEG) conjugated to the targeting ligand folate (FA) for multimodal imaging-guided combined chemo-photothermal therapy. Upon PEG modification, the small IrSx NPs (about 4 nm) self-assembled into much larger (about 120 nm) IrSx-PEG-FA NPs, which exhibited high photostability, ideal photothermal effect, high drug loading and pH-/photothermal-responsive drug release properties. By using the model anticancer drug camptothecin (CPT), we demonstrated that CPT@IrSx-PEG-FA can effectively target FA-receptor-positive cancer cells in vitro and show efficient tumor accumulation in vivo. The combination of CPT@IrSx-PEG-FA treatment and irradiation with an 808 nm laser resulted in complete tumor elimination. Moreover, photothermal/photoacoustic (PA)/computed tomography (CT) imaging provided an effective means to monitor the therapeutic effects. Interestingly, the nanoparticles can be cleared, resulting in low systematic toxicity of CPT@IrSx-PEG-FA. Our work demonstrates that the as-prepared IrSx-PEG-FA NPs present a promising platform for the construction of multifunctional theranostic agents for cancer therapy.


Asunto(s)
Camptotecina/administración & dosificación , Receptor 1 de Folato/química , Nanopartículas/química , Fototerapia , Polietilenglicoles/química , Animales , Antineoplásicos/administración & dosificación , Materiales Biocompatibles/química , Línea Celular Tumoral , Terapia Combinada , Doxorrubicina/administración & dosificación , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Ácido Fólico , Células HeLa , Humanos , Concentración de Iones de Hidrógeno , Hipertermia Inducida , Iridio , Células MCF-7 , Ratones , Imagen Multimodal , Nanopartículas/uso terapéutico , Técnicas Fotoacústicas , Sulfuros , Nanomedicina Teranóstica , Tomografía Computarizada por Rayos X
17.
Zootaxa ; 4339(1): 1-77, 2017 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-29245724

RESUMEN

Eight new species of the subgenus Pseudocypus Mulsant & Rey, 1876 of the genus Ocypus Leach, 1819 (Coleoptera, Staphylinidae, Staphylinini) are described from China: O. (Pseudocypus) pileaticulminis sp. nov., O. (Pseudocypus) denticulminis sp. nov., O. (Pseudocypus) anguliculminis sp. nov., O. (Pseudocypus) digiticulminis sp. nov., O. (Pseudocypus) alticulminis sp. nov., O. (Pseudocypus) fusciculminis sp. nov., O. (Pseudocypus) nigriculminis sp. nov. and O. (Pseudocypus) recticulminis sp. nov. Line drawings and color illustrations of adult structures and genitalia are given for all new species and the following species recorded in China: O. (Pseudocypus) aenescens Eppelsheim, 1889, O. (Pseudocypus) ballio Smetana, 2007, O. (Pseudocypus) calamis Smetana, 2007, O. (Pseudocypus) densissimus (Bernhauer, 1933), O. (Pseudocypus) dolon Smetana, 2007, O. (Pseudocypus) graeseri Eppelsheim, 1887, O. (Pseudocypus) hecato Smetana, 2007, O. (Pseudocypus) inexspectatus Eppelsheim, 1887 (new record in China), O. (Pseudocypus) menander Smetana, 2007, O. (Pseudocypus) neocles Smetana, 2007, O. (Pseudocypus) orodes Smetana, 2007, O. (Pseudocypus) pelias Smetana, 2007, O. (Pseudocypus) puer (Smetana, 2005a), O. (Pseudocypus) picipennis (Fabricius, 1793), O. (Pseudocypus) rhinton Smetana, 2007, and O. (Pseudocypus) semenowi Reitter, 1887. A key to Chinese species of the subgenus Pseudocypus Mulsant & Rey, 1876 is also provided in the text.


Asunto(s)
Escarabajos , Distribución Animal , Estructuras Animales , Animales , China , Tamaño de los Órganos
18.
Colloids Surf B Biointerfaces ; 143: 342-351, 2016 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-27022875

RESUMEN

Biomaterials are being extensively used in various biomedical fields; however, they are readily infected with microorganisms, thus posing a serious threat to the public health care. We herein presented a facile route to the antibacterial modification of an important A-B-A type biomaterial using poly (ethylene glycol) methyl ether (mPEG)- poly(ε-caprolactone) (PCL)-mPEG as a typical model. Inexpensive, commercial bis(2-hydroxyethyl) methylammonium chloride (DMA) was adopted as an antibacterial unit. The effective synthesis of the antibacterial copolymer mPEG-PCL-∼∼∼-PCL-mPEG (where ∼∼∼ denotes the segment with DMA units) was well confirmed by FTIR and (1)H NMR spectra. At an appropriate modification extent, the DMA unit could render the copolymer mPEG-PCL-∼∼∼-PCL-mPEG highly antibacterial, but did not largely alter its fascinating intrinsic properties including the thermosensitivity (e.g., the body temperature-induced sol-gel transition), non-cytotoxicity, and controlled drug release. A detailed study on the sol-gel-sol transition behavior of different copolymers showed that an appropriate extent of modification with DMA retained a sol-gel-sol transition, despite the fact that a too high extent caused a loss of sol-gel-sol transition. The hydrophilic and hydrophobic balance between mPEG and PCL was most likely broken upon a high extent of quaternization due to a large disturbance effect of DMA units at a large quantity (as evidenced by the heavily depressed PCL segment crystallinity), and thus the micelle aggregation mechanism for the gel formation could not work anymore, along with the loss of the thermosensitivity. The work presented here is highly expected to be generalized for synthesis of various block copolymers with immunity to microorganisms. Light may also be shed on understanding the phase transition behavior of various multiblock copolymers.


Asunto(s)
Antibacterianos/química , Preparaciones de Acción Retardada , Epidermis/efectos de los fármacos , Poliésteres/química , Polietilenglicoles/química , Antibacterianos/farmacología , Biodegradación Ambiental , Temperatura Corporal , Catárticos/metabolismo , Supervivencia Celular/efectos de los fármacos , Liberación de Fármacos , Emodina/análogos & derivados , Emodina/metabolismo , Epidermis/metabolismo , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Geles , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Inyecciones , L-Lactato Deshidrogenasa/metabolismo , Micelas , Transición de Fase , Poliésteres/farmacología , Polietilenglicoles/farmacología , Piel Artificial , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Temperatura de Transición
19.
Medicine (Baltimore) ; 94(45): e1994, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26559288

RESUMEN

To evaluate the efficacy of computed tomography (CT) guided single radiofrequency thermocoagualtion (RFT) in 1137 patients with idiopathic trigeminal neuralgia after a follow-up period of 11 years, specially focused on duration of pain relief in different branches of trigeminal nerve, side effect, and complications. Retrospective study of patients with idiopathic trigeminal neuralgia treated with a single CT guided RFT procedure between January 2002 and December 2013. The mean follow-up time was 46.14 ±â€Š30.91 months. Immediate postprocedure pain relief was 98.4%. V2 division obtained the best pain relief rate: 91%, 89%, 80%, 72%, 60%, and 54% at 1, 3, 5, 7, 9, and 11 years, respectively. No statistical difference pairwise comparison was in other groups. The complications included masseter muscle weakness, corneitis, diplopia, ptosis, hearing loss, limited mouth opening, and low pressure headache. Masticatory weakness mostly occurred in patients with V3 branch involvement, while Corneitis and Diplopia all in patients with V1 branch involvement. No mortalities observed during or after RFT. All different branches division of trigeminal neuralgia achieved comparable satisfactory curative effect; V2 obtained the best excellent pain relief, after RFT procedure. Facial numbness is inevitable after RFT, which patients who have pain in all 3 trigeminal divisions and patients who desire no facial numbness should be cautious. Masticatory weakness is mainly related with V3 injured, while Corneitis and Diplopia in patients with V1 injured by RFT.


Asunto(s)
Electrocoagulación/métodos , Neuralgia del Trigémino/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Radiografía Intervencional/métodos , Recurrencia , Estudios Retrospectivos , Nervio Trigémino/patología , Adulto Joven
20.
Carbohydr Polym ; 91(1): 305-13, 2013 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-23044137

RESUMEN

In this study, a commercial chitosan cross-linked with glutaraldehyde (GA-chitosan) having the autofluorescent property was effectively blended with a poly (vinyl alcohol) (PVA) matrix, in the formation of a transparent and fluorescent blend film. The fluorescent efficiency of the film was enhanced with red-shifted emission band by increasing the concentrations of the GA-chitosan and decreasing the PVA crystallinity. It was found that the incorporation of silica nanoparticles could further decrease the PVA crystallinity, enhance the fluorescent efficiency, and largely redshift the emission band, as compared with the neat GA-chitosan-PVA blend film. This fluorescent property could be finely tuned by careful doping of the silica nanoparticles and change of the PVA crystallinity. These phenomena could be reasonably explained by high extent of isolation of the fluorophores, increase of the stiffness of the fluorescent conjugated planar structure, and further decrease of the PVA crystallinity. In addition, the introduction of the nano-silica could improve the water and heat resistances of the GA-chitosan-PVA based silica nanocomposites.


Asunto(s)
Quitosano/química , Portadores de Fármacos/química , Colorantes Fluorescentes/química , Glutaral/química , Nanocompuestos/química , Alcohol Polivinílico/química , Dióxido de Silicio/química , Espectrometría de Fluorescencia
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