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1.
Nat Commun ; 15(1): 1092, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38316772

RESUMEN

Demands on superhydrophobic, self-cleaning and piezoelectric membranes have gained significantly due to their potential to overcome global shortages in clean water and energy. In this study, we have discovered a novel plasma-assisted nonsolvent induced phase separation (PANIPS) method to prepare superhydrophobic, self-cleaning and piezoelectric poly(vinylidene difluoride) (PVDF) membranes without additional chemical modifications or post-treatments. The PANIPS membranes exhibit water contact angles ranging from 151.2° to 166.4° and sliding angles between 6.7° and 29.7°. They also show a high piezoelectric coefficient (d33) of 10.5 pC N-1 and can generate a high output voltage of 10 Vpp. The PANIPS membranes can effectively recover pure water from various waste solutions containing Rose Bengal dye, humic acid, or sodium dodecyl sulfate via direct contact membrane distillation (DCMD). This study may provide valuable insights to fabricate PANIPS membranes and open up new avenues to molecularly design advanced superhydrophobic, self-cleaning, and piezoelectric membranes in the fields of clean water production, motion sensor, and piezoelectric nanogenerator.

2.
ACS Omega ; 7(48): 44085-44092, 2022 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-36506144

RESUMEN

There is a growing interest in the fabrication of membranes and packaging materials from natural resources for a sustainable society. A regenerated cellulose (RC) film composed solely of cellulose has outstanding advantages including biodegradability, transparency, mechanical strength, and thermal stability. To expand the application of the RC film, various surface modification methods have been proposed. However, conventional chemical methods have disadvantages such as environmental burden and difficulty in controlling the reaction. In this work, low-pressure plasma treatment, a green, solvent-free, and easily controllable approach, was performed for surface modification of the RC film. The effects of three different plasma species (O2, N2, and CF4) and treatment conditions on the surface properties of RC films were investigated based on water contact angle measurements, chemical composition analysis, and surface topography. O2 and N2 plasma treatment slightly enhanced the surface wettability of RC films due to the etching by the plasma reactive species and the formation of new hydrophilic functional groups. In CF4 plasma treatments, the hydrophobic surface with a contact angle of 120.6° was obtained in a short treatment time (60 s) owing to the deposition of fluorocarbon groups on the surface. However, the treated surface in a longer reaction time resulted in increased wettability due to the diffusion and degradation of fluorine-containing bonds. The new insights could be valuable for further studies of surface modification and functionalization of RC films.

3.
Biomedicines ; 10(8)2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-36009524

RESUMEN

Photodynamic therapy (PDT)-based cancer vaccines are shown to be more effective modalities for treating cancer in animal models compared to other methods used to generate cancer cell-derived vaccines. The higher efficacy seems to stem from the generation of cell membrane nanovesicles or fragments that carry both cancer cell-specific antigens and high surface content of damage-associated molecular pattern (DAMP) molecules induced by oxidative stress. To develop more effective cancer vaccines in this direction, we explored the generation of cancer vaccines by applying different sources of oxidative stress on cancer cell cultures followed by spontaneous release or filter extrusions to produce cancer cell-derived DAMP-expressing nanovesicles. Through an in-vitro test based on the co-culture of cancer cells and macrophages, it was found that the nanovesicle vaccines generated by H2O2 are as effective as those generated by PDT in diminishing cancer cell culture masses, providing a simpler way to manufacture vaccines. In addition, the nanovesicle vaccines produced by filter extrusion are as potent as those produced by spontaneous release, rendering a more stable way for vaccine production.

4.
Anal Chem ; 94(23): 8209-8216, 2022 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-35652456

RESUMEN

Axial view liquid electrode plasma-atomic emission spectrometry (axial view LEP-AES) was proposed and fabricated successfully in this work. The emission spectra from Zn, Cd, Pb, Ca, and K were applied for characterization and optimization. Comparing with conventional radial view LEP-AES devices, the newly designed axial view-LEP provided better sensing ability toward trace heavy metals. Moreover, pulsed voltage discharge was found to be advantageous over continuous discharge under the same discharge time for detection. The optimized parameters facilitate the limit of detection to achieve 0.24, 0.051, and 0.85 µg L-1 for Zn, Cd, and Pb, respectively. Furthermore, the axial view LEP-AES possessed excellent reproducibility and good durability. The real sample tests using two different certified reference water samples revealed the great potential of the axial view LEP-AES as a novel practical elemental analysis tool.


Asunto(s)
Cadmio , Oligoelementos , Cadmio/análisis , Electrodos , Plomo , Reproducibilidad de los Resultados , Espectrofotometría Atómica/métodos , Análisis Espectral , Oligoelementos/análisis , Zinc/análisis
5.
ACS Appl Mater Interfaces ; 14(14): 16136-16146, 2022 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-35352549

RESUMEN

A solid-state lithium metal battery of low capacity fade is acquired using the electrolyte membrane of a polyurethane-acrylate-thiocarbonate (PUAT) oligomer, macromolecules, lithium salt, and an oxide additive. Two types of composite electrolytes have been prepared: the free-standing electrolyte (PUAT-FS) and the electrode-coated electrolyte (PUAT-EC). Featuring a less PUAT content and a finer granular size, PUAT-FS is less ion-conductive than PUAT-EC; 0.44 mS cm-1 in contrast to 0.51 mS cm-1 at room temperature. Nonetheless, the lithium iron phosphate battery of PUAT-FS is far superior to that of PUAT-EC in terms of cycling stability. When cycled at 0.1C and room temperature, the PUAT-FS battery reaches a maximum discharge capacity of 169.7 mAh g-1 at its 20th cycle and decreases to 141.0 mAh g-1 at the 500th cycle, 83.1% retention. The capacity fading rate of the PUAT-FS battery is 0.034% per cycle at 0.1C, significantly less than that of the PUAT-EC battery, 0.138% per cycle. Other maximum capacities and fading rates of the PUAT-FS battery are 152.5 mAh g-1 and 0.050% per cycle at 0.2C in 800 cycles and 126.1 mAh g-1 and 0.051% per cycle at 0.5C in 1000 cycles. These features of a low fading rate and high capacity are attributed to a balanced ratio of oligomer to macromolecule (1:1 w/w) in the free-standing electrolyte and the sulfur-containing oligomer.

6.
Sci Rep ; 12(1): 1812, 2022 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-35110659

RESUMEN

The induction and direction of stem cell differentiation into needed cell phenotypes is the central pillar of tissue engineering for repairing damaged tissues or organs. Conventionally, a special recipe of chemical factors is formulated to achieve this purpose for each specific target cell type. In this work, it is demonstrated that the combination of extrinsic photobiomodulation and collagen-covered microislands could be used to induce differentiation of Wharton's jelly mesenchymal stem cells (WJ-MSCs) with the differentiation direction dictated by the specific island topography without use of chemical factors. Both neurogenic differentiation and adipogenic differentiation could be attained with a rate surpassing that using chemical factors. Application of this method to other cell types is possible by utilizing microislands with a pattern tailored particularly for each specific cell type, rendering it a versatile modality for initiating and guiding stem cell differentiation.


Asunto(s)
Adhesión Celular , Diferenciación Celular/efectos de la radiación , Colágeno/fisiología , Luz , Células Madre Mesenquimatosas/efectos de la radiación , Ingeniería de Tejidos , Adipogénesis/efectos de la radiación , Técnicas de Cultivo de Célula , Células Cultivadas , Humanos , Células Madre Mesenquimatosas/fisiología , Neurogénesis/efectos de la radiación , Gelatina de Wharton/citología
7.
Molecules ; 26(22)2021 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-34833852

RESUMEN

Atmospheric pressure chemical ionization (APCI)-mass spectrometry (MS) and electrospray ionization (ESI)-MS can cover the analysis of analytes from low to high polarities. Thus, an ion source that possesses these two ionization functions is useful. Atmospheric surface-assisted ionization (ASAI), which can be used to ionize polar and nonpolar analytes in vapor, liquid, and solid forms, was demonstrated in this study. The ionization of analytes through APCI or ESI was induced from the surface of a metal substrate such as a titanium slab. ASAI is a contactless approach operated at atmospheric pressure. No electric contacts nor any voltages were required to be applied on the metal substrate during ionization. When placing samples with high vapor pressure in condensed phase underneath a titanium slab close to the inlet of the mass spectrometer, analytes can be readily ionized and detected by the mass spectrometer. Furthermore, a sample droplet (~2 µL) containing high-polarity analytes, including polar organics and biomolecules, was ionized using the titanium slab. One titanium slab is sufficient to induce the ionization of analytes occurring in front of a mass spectrometer applied with a high voltage. Moreover, this ionization method can be used to detect high volatile or polar analytes through APCI-like or ESI-like processes, respectively.


Asunto(s)
Presión Atmosférica , Espectrometría de Masa por Ionización de Electrospray , Titanio
8.
Polymers (Basel) ; 13(7)2021 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-33808445

RESUMEN

Chitosan nanofiber has a highly uniform structure of 20-50 nm in diameter and shows high dispersibility in water due to its submicron size and high surface-to-volume ratio. The stacked nanofibers film is useful for breathability because it has a gap with a size of several tens of nm or more. However, the chemical bonds between the nanofibers cannot be broken during use. In this study, the thin films were obtained by filtration of chitosan nanofibers and 3-glycidoxypropyltrimethoxysilane (GPTMS) mixture. The addition of GPTMS changed the wettability, mechanical property and stability in water of the thin films. Bacitracin zinc salt (BZ) has been used for the localized dermatological medicines and loaded in the films. BZ interacted electrostatically with the thin films matrix and the release of BZ was controlled by the amount of GPTMS. A higher released amount of BZ showed higher antibacterial effects toward S. aureus. The film was also tested their toxicity by L929 fibroblasts. The release of less than 11.9 µg of BZ showed antibacterial effects, but were not toxic for fibroblast cells.

9.
Materials (Basel) ; 13(21)2020 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-33172217

RESUMEN

Surface modification on microporous polyethylene (PE) membranes was facilitated by plasma polymerizing with two hydrophilic precursors: ethylene oxide vinyl ether (EO1V) and diethylene oxide vinyl ether (EO2V) to effectively improve the fouling against mammalian cells (Chinese hamster ovary, CHO cells) and proteins (bovine serum albumin, BSA). The plasma polymerization procedure incorporated uniform and pin-hole free ethylene oxide-containing moieties on the filtration membrane in a dry single-step process. The successful deposition of the plasma polymers was verified by Fourier-transform infrared (FTIR), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) analyses. Water contact angle measurements and permeation experiments using cell and protein solutions were conducted to evaluate the change in hydrophilicity and fouling resistance for filtrating biomolecules. The EO1V and EO2V plasma deposited PE membranes showed about 1.45 fold higher filtration performance than the pristine membrane. Moreover, the flux recovery reached 80% and 90% by using deionized (DI) water and sodium hydroxide (NaOH) solution, indicating the efficacy of the modification and the good reusability of the modified PE membranes.

10.
Int J Pharm ; 566: 708-716, 2019 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-31212056

RESUMEN

In this study, a facile, economically feasible, and scalable approach to fabricate macroporous poly(vinyl alcohol)-GO (PVA-GO) nanocomposite films with varying filler loadings was demonstrated. The nanocomposite films were prepared using a solvent casting process and employed as a diffusion layer for modulating the transdermal delivery of an anti-inflammatory drug (i.e., ketoprofen). The diffusion membrane was assembled in a three-layer structure with PVA/PVA-GO films between ketoprofen-loaded cellulose and cellulose acetate to mimic skin barrier. Through the incorporation of GO sheets into PVA matrix, the mass diffusion and drug release rate of ketoprofen could be modulated to attain a controlled-release system within period in comparison to that of neat PVA film, which showed more rapid release. It was observed that the dispersion level of GO sheets in the polymer matrix played a crucial role to slow the diffusion rate and drug release, where 3 wt% filler loading gave the slowest rate of release. The results from the present study shed light on the mechanism of and may provide guidelines for modulating drug release rates of NSAID in film-based delivery vehicles for transdermal delivery applications.


Asunto(s)
Antiinflamatorios no Esteroideos/química , Grafito/química , Cetoprofeno/química , Nanocompuestos/química , Óxidos/química , Alcohol Polivinílico/química , Administración Cutánea , Sistemas de Liberación de Medicamentos , Liberación de Fármacos
11.
Talanta ; 194: 837-845, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30609613

RESUMEN

Microfluidic paper-based analytical devices (µPADs) have recently emerged as a simple, portable, user-friendly, and affordable alternative to more instrument-intensive analytical approaches for point-of-care testing (POCT), food safety analysis, and environmental monitoring. However, most of the existing methods for the fabrication of µPADs still face a great challenge because of different trade-offs among cost, convenience, and the pattern resolution. In this work, we report a facile one-step approach to prepare a µPAD using an affordable, easy-to-build 3D printer to generate patterns of solid wax on laboratory filter paper. The presented wax printing method did not require the use of predesigned masks and an external heat source to form complete hydrophobic wax barrier through the use of a custom-made extruder. The results revealed a strong linear relationship (R2 = 0.985) between the nominal and the printed widths of the wax barriers. The achievable resolution of the wax barrier printed on filter paper was 468 ±â€¯72 µm, which was lower than previously reported minimum barrier feature sizes achieved by wax printing and other wax patterning techniques, such as stamping and screen-printing. The analytical utility of the fabricated µPADs was evaluated for colorimetric nitrite and glucose detection in artificial solutions. It was found that the fabricated µPADs provided adequate accuracy and reproducibility for quantitative determination of nitrite and glucose within concentration ranges relevant to the disease detection in human saliva and urine. The wax printing approach reported here provides a simple, rapid, and cost-effective fabrication method for paper-based microfluidics and may bring benefits to medical diagnostics in the developing world.


Asunto(s)
Colorimetría/instrumentación , Glucosa/análisis , Dispositivos Laboratorio en un Chip , Nitritos/análisis , Papel , Impresión Tridimensional/instrumentación , Ceras/química
12.
ACS Appl Bio Mater ; 1(5): 1579-1586, 2018 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-34996208

RESUMEN

Herein, the novel strategy of copper oxide (CuO) deposited oxygen-doped nitrogen incorporated nanodiamond (NOND)/Si pyramids (Pyr-Si) heterostructure is studied for high-performance nonenzymatic glucose sensor. The combined properties of surface-modified NOND/Pyr-Si induced by different growth durations (5 to 20 min) of CuO is envisioned to improve glucose sensitivity and stability. For comparison, the same methods and parameters were deposited on the plane silicon wafers. The systematic analysis reveals the best glucose sensing properties of 15 min grown CuO/NOND/Pyr-Si based sensor, with a high sensitivity of 1993 µA mM-1 cm-2, a lower limit of detection of 0.1 µm, and a longer stability of 28 d (∼96%). In addition, the present sensor exhibits good selectivity of glucose among other analytes such as sodium chloride, ascorbic acid, uric acid, and so on. The enhancement in glucose sensing performances of the as-fabricated CuO/NOND/Pyr-Si is ascribed to the interfacial effect of NOND and the synergistic effect of CuO and NOND/Pyr-Si. Moreover, the oxygen dopant in NOND and CuO stimulates the reactive oxygen species while measuring glucose and affords rapid recovery (<2 s). This promotes fast electron kinetics in the electrocatalytic solutions, which enhances the electroactive area and thereby contributes to a high sensitivity. These salient results suggested that the as-fabricated CuO/NOND/Pyr-Si sensor is more suitable for high-performance biosensors and effective energy storage device applications.

13.
J Tissue Eng Regen Med ; 12(4): 1111-1122, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29134783

RESUMEN

The incorporation of inorganic materials into electrospun nanofibres has recently gained considerable attention for the development of extracellular matrix-like scaffolds with improved mechanical properties and enhanced biological functions for tissue engineering applications. In this study, polymer-inorganic composite fibres consisting of poly(2-ethyl-2-oxazoline) (PEOXA) and tetrabutyl titanate as the titanium precursor were successfully fabricated through a combined sol-gel/electrospinning approach. PEOXA/Ti(OR)n composite fibres were obtained with varying amounts of polymer and titanium precursors. Calcinations of the composite fibres were performed at varying temperatures to produce TiO2 fibres (TiO2 -T-60) with anatase, anatase/rutile mixed phase, and rutile crystal structures. Thin polymer films (i.e., poly(2-ethyl-2-oxazoline) (PEOXA), polycaprolactone (PCL), and poly(methyl methacrylate) (PMMA)) were subsequently deposited onto TiO2 -T-60 fibre mats by spin coating to facilitate handling of the electrospun substrates after calcination, which are rather brittle and disintegrate easily, and to probe cell-materials interactions. The cellular behaviour of mouse L929 fibroblasts after culture periods of 1-5 days was compared on the following fibre scaffolds: PEOXA/Ti(OR)n , TiO2 -T-60 (T = 600, 650, and 700 °C), TiO2 -T-60 spin-coated with thin PCL film (PCL/TiO2 -T-60), and pure PCL. The results obtained from in vitro cell culture studies for the lactate dehydrogenase release assay and confocal microscopic visualization pointed out the synergistic interplay between the TiO2 crystal structure and spin-coated PCL film in facilitating cell interactions with the scaffold surface. The L929 cells were observed to adhere and proliferate better on the surface of TiO2 -700-60 having the rutile structure than on the surfaces of TiO2 -600-60 and TiO2 -650-60 fibre scaffolds with anatase and anatase/rutile mixed phase structures, respectively.


Asunto(s)
Adhesión Celular , Proliferación Celular , Fibroblastos/metabolismo , Nanofibras/química , Andamios del Tejido/química , Titanio/química , Animales , Línea Celular , Fibroblastos/citología , Ratones
14.
Mol Med Rep ; 17(1): 2061-2069, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29138834

RESUMEN

Oxygen free radicals have been implicated in the pathogenesis of toxic liver injury and are thought to be involved in cardiac dysfunction in the cirrhotic heart. Therefore, direct evidence for the electron spin resonance (ESR) detection of how D­galactosamine (GalN), an established experimental hepatotoxic substance, induced free radicals formation in platelets and primary hepatocytes is presented in the present study. ESR results demonstrated that GalN induced hydroxyl radicals (OH•) in a resting human platelet suspension; however, radicals were not produced in a cell free Fenton reaction system. The GalN­induced OH• formation was significantly inhibited by the cyclooxygenase (COX) inhibitor indomethasin, though it was not affected by the lipoxygenase (LOX) or cytochrome P450 inhibitors, AA861 and 1­aminobenzotriazole (ABT), in platelets. In addition, the present study demonstrated that baicalein induced semiquinone free radicals in platelets, which were significantly reduced by the COX inhibitor without affecting the formed OH•. In the mouse primary hepatocytes, the formation of arachidonic acid (AA) induced carbon­centered radicals that were concentration dependently enhanced by GalN. These radicals were inhibited by AA861, though not affected by indomethasin or ABT. In addition, GalN did not induce platelet aggregation prior to or following collagen pretreatment in human platelets. The results of the present study indicated that GalN and baicalein may induce OH• by COX and LOX in human platelets. GalN also potentiated AA induced carbon­centered radicals in hepatocytes via cytochrome P450. The present study presented the role of free radicals in the pathophysiological association between platelets and hepatocytes.


Asunto(s)
Plaquetas/metabolismo , Radicales Libres/metabolismo , Hepatocitos/metabolismo , Animales , Plaquetas/efectos de los fármacos , Células Cultivadas , Espectroscopía de Resonancia por Spin del Electrón , Galactosamina/toxicidad , Hepatocitos/efectos de los fármacos , Humanos , Masculino , Ratones Endogámicos C57BL , Estrés Oxidativo , Agregación Plaquetaria , Cultivo Primario de Células
15.
Nanotechnology ; 28(35): 355703, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28649960

RESUMEN

The application of the electrospun nanomaterials to surface-enhanced Raman spectroscopy (SERS) is a rapidly evolving field which holds potential for future developments in the generation of portable plasmonic-based detection platforms. In this study, a simple approach to fabricate electrospun poly(N-vinylpyrrolidone) (PVP) mats decorated with gold nanoparticles (AuNPs) by combining electrospinning and calcination was presented. AuNPs were decorated on the fiber mat surface through electrostatic interactions between positively charged aminosilane groups and negatively charged AuNPs. The size and coverage density of AuNPs on the fiber mats could be tuned by varying the calcination temperature. Calcination of AuNPs-decorated PVP fibers at 500 °C-700 °C resulted in the uniform decoration of high density AuNPs with very narrow gaps on every single fiber, which in turn contribute to strong electromagnetic SERS enhancement. The robust free-standing AuNPs-decorated mat which calcined at 500 °C (500/AuNPs-F) exhibited high SERS activity toward cationic (methylene blue, MB) and anionic (methyl orange, MO) dyes in single and binary systems with a detection range from tens of nM to a few hundred µM. The fabricated SERS substrate demonstrated high reproducibility with the spot-to-spot variation in SERS signal intensities was ±10% and ±12% for single and binary dye systems, respectively. The determination of MB and MO in spiked river water and tap water with 500/AuNPs-F substrate gave satisfactory results in terms of the percent spike recoveries (ranging from 92.6%-96.6%) and reproducibility (%RSD values less than 15 for all samples).

16.
Int J Pharm ; 516(1-2): 158-169, 2017 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-27989821

RESUMEN

Curcumin (CUR) has a wide spectrum of biological and pharmacological activities, yet problems of its bioavailability remained a major challenge in preclinical studies. Thus, the design of the delivery systems with CUR as a model drug featuring dual release process - an initial burst followed by sustained release - to provide the optimal drug pharmacokinetics in the therapeutic region has been actively pursued. In this study, the 3-aminopropyltriethoxysilane (APTES)-functionalized electrospun poly(N-vinyl-2-pyrrolidone) fibers (NH2-PVP) were utilized as a free-standing substrate for the immobilization of CUR-PVP capped gold nanoparticles (CUR-PGNPs) conjugates. The conjugate was synthesized by sonication and the drug entrapment percentage was determined to be 54.2 ±1.8. CUR-PGNPs immobilized on NH2-PVP fibers showed a moderate burst release during the first few hours, followed by a sustained release lasting for 2days. The drug release was found pH-dependent (pH 5.0>6.0>7.4). The two-stage release profiles of CUR-PGNPs@NH2-PVP fibers were fitted well to Korsmeyer-Peppas model, indicating a non-Fickian diffusion mechanism for initial burst release and Fickian diffusion-controlled mechanism for the sustained release. Initial biocompatibility assessments based on lactate dehydrogenase (LDH) assay and morphological examination by SEM with L-929 mouse fibroblasts revealed that CUR-PGNPs@NH2-PVP nanofibrous scaffold was capable of supporting cell growth over a culture period of 3days.


Asunto(s)
Curcumina/administración & dosificación , Sistemas de Liberación de Medicamentos , Nanopartículas del Metal , Propilaminas/química , Silanos/química , Animales , Línea Celular , Química Farmacéutica/métodos , Curcumina/química , Preparaciones de Acción Retardada , Liberación de Fármacos , Fibroblastos/metabolismo , Oro , Concentración de Iones de Hidrógeno , L-Lactato Deshidrogenasa/metabolismo , Ratones , Polivinilos/química , Pirrolidinas/química , Factores de Tiempo
17.
Phytother Res ; 30(2): 214-21, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26560814

RESUMEN

Nobiletin, a bioactive polymethoxylated flavone (5,6,7,8,3(') ,4(') -hexamethoxyflavone), is abundant in citrus fruit peel. Although nobiletin exhibits antitumor activity against various cancer cells, the effect of nobiletin on glioma cells remains unclear. The aim of this study was to determine the effects of nobiletin on the human U87 and Hs683 glioma cell lines. Treating glioma cells with nobiletin (20-100 µm) reduced cell viability and arrested the cell cycle in the G0/G1 phase, as detected using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and propidium iodide (PI) staining, respectively; however, nobiletin did not induce cell apoptosis according to PI-annexin V double staining. Data from western blotting showed that nobiletin significantly attenuated the expression of cyclin D1, cyclin-dependent kinase 2, cyclin-dependent kinase 4, and E2 promoter-binding factor 1 (E2F1) and the phosphorylation of Akt/protein kinase B and mitogen-activated protein kinases, including p38, extracellular signal-regulated kinase, and c-Jun N-terminal kinase. Our data also showed that nobiletin inhibited glioma cell migration, as detected by both functional wound healing and transwell migration assays. Altogether, the present results suggest that nobiletin inhibits mitogen-activated protein kinase and Akt/protein kinase B pathways and downregulates positive regulators of the cell cycle, leading to subsequent suppression of glioma cell proliferation and migration. Our findings evidence that nobiletin may have potential for treating glioblastoma multiforme.


Asunto(s)
Puntos de Control del Ciclo Celular/efectos de los fármacos , Flavonas/farmacología , Glioma/patología , Transducción de Señal/efectos de los fármacos , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Citrus/química , Quinasa 2 Dependiente de la Ciclina/metabolismo , Quinasa 4 Dependiente de la Ciclina/metabolismo , Factor de Transcripción E2F1/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Fosforilación , Proteínas Proto-Oncogénicas c-akt/metabolismo
18.
Molecules ; 20(5): 8198-212, 2015 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-25961161

RESUMEN

Abnormal proliferation of vascular smooth muscle cells (VSMCs) is important in the pathogenesis of vascular disorders such as atherosclerosis and restenosis. Hinokitiol, a tropolone derivative found in Chamacyparis taiwanensis, has been found to exhibit anticancer activity in a variety of cancers through inhibition of cell proliferation. In the present study, the possible anti-proliferative effect of hinokitiol was investigated on VSMCs. Our results showed that hinokitiol significantly attenuated the PDGF-BB-stimulated proliferation of VSMCs without cytotoxicity. Hinokitiol suppressed the expression of proliferating cell nuclear antigen (PCNA), a maker for cell cycle arrest, and caused G0/G1 phase arrest in cell cycle progression. To investigate the mechanism underlying the anti-proliferative effect of hinokitiol, we examined the effects of hinokitiol on phosphorylations of Akt, ERK1/2, p38 and JNK1/2. Phospholipase C (PLC)-γ1 phosphorylation, its phosphorylated substrates and p27kip1 expression was also analyzed. Pre-treatment of VSMCs with hinikitiol was found to significantly inhibit the PDGF-BB-induced phosphorylations of JNK1/2 and PLC-γ1, however no effects on Akt, ERK1/2, and p38. The up-regulation of p27kip1 was also observed in hinokitiol-treated VSMCs. Taken together, our results suggest that hinokitiol inhibits PDGF-BB-induced proliferation of VSMCs by inducing cell cycle arrest, suppressing JNK1/2 phosphorylation and PLC-γ1, and stimulating p27kip1 expression. These findings suggest that hinokitiol may be beneficial for the treatment of vascular-related disorders and diseases.


Asunto(s)
Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Monoterpenos/farmacología , Músculo Liso Vascular/efectos de los fármacos , Miocitos del Músculo Liso/efectos de los fármacos , Fosfolipasa C gamma/metabolismo , Proteínas Proto-Oncogénicas c-sis/farmacología , Tropolona/análogos & derivados , Tropolona/farmacología , Animales , Becaplermina , Puntos de Control del Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/metabolismo , Fase G1/efectos de los fármacos , Masculino , Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/metabolismo , Fosforilación/efectos de los fármacos , Antígeno Nuclear de Célula en Proliferación/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Ratas Wistar , Fase de Descanso del Ciclo Celular/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
19.
Langmuir ; 30(47): 14257-62, 2014 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-25377994

RESUMEN

A surface that resists protein adsorption and cell adhesion is highly desirable for many biomedical applications such as blood-contact devices and biosensors. In this study, we fabricated a carboxybetaine-containing surface and evaluated its antifouling efficacy. First, an amine-containing substrate was created by chemical vapor deposition of 4-aminomethyl-p-xylylene-co-p-xylylene (Amino-PPX). Aldehyde-ended carboxybetaine molecules were synthesized and conjugated onto Amino-PPX. The carboxybetaine-PPX surface greatly reduced protein adsorption and cell adhesion. The attachment of L929 cells on the carboxybetaine-PPX surface was reduced by 87% compared to the cell adhesion on Amino-PPX. Furthermore, RGD peptides could be conjugated on carboxybetaine-PPX to mediate specific cell adhesion. In conclusion, we demonstrate that a surface decoration with monocarboxybetaine molecules is useful for antifouling applications.


Asunto(s)
Compuestos de Anilina/química , Betaína/química , Polímeros/química , Proteínas/química , Adsorción , Adhesión Celular/efectos de los fármacos , Propiedades de Superficie
20.
PLoS One ; 9(1): e87100, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24498022

RESUMEN

AIM: Our goal was to investigate the relationship between clinical status and the presence of carious or periodontal pathogens among parent-child familial pairs. Clinical practices of risk assessment with consideration of familial pathogen interaction might reduce the need for therapy, improve patient outcomes, and ultimately reduce oral disease burden. MATERIALS AND METHODS: In this study, we enrolled 30 parent-child pairs, with the children exhibiting complete deciduous dentition or mixed dentition with only permanent first molars. Clinical statuses were evaluated using caries and periodontal disease indicators, including the sum of decay and the number of missing or filled teeth (DMFT) for adults, decay, extraction caused by dental disease, and filled teeth (deft), for children, probing depth, and plaque control record (PCR). Supra- and sub-gingival bacteria were determined based on semi-quantitative measurements of microbial infection by using data from the Dentocult(®) SM test (caries-related organisms) and the PerioCheck(®) test (periodontal disease-related organisms). RESULTS: No statistically significant relationship was detected between the prevalence of periodontal pathogens and that of cariogenic pathogens in the oral cavity. However, the clinical status of caries (DMFT) was negatively correlated with the clinical status of periodontal disease (pocket depth) in parents who were infected with dominant periodontal pathogens (r = -0.59, p<0.01). Parents' DMFT scores were positively correlated with children's deft and PCR scores. PCR and deft scores of children appeared to decrease significantly with the parent's pocket depth. CONCLUSION: The study showed that the quantity of caries pathogens were not significant related to periodontal pathogens, but the caries clinical outcome is negative related with periodontal clinical outcome between familial pairs.


Asunto(s)
Caries Dental/microbiología , Adulto , Niño , Preescolar , Índice CPO , Caries Dental/diagnóstico , Caries Dental/epidemiología , Placa Dental/diagnóstico , Placa Dental/epidemiología , Placa Dental/microbiología , Femenino , Humanos , Masculino , Padres , Prevalencia , Diente Primario/microbiología
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