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1.
Respir Res ; 23(1): 93, 2022 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-35413838

RESUMEN

BACKGROUND: Non-small cell lung cancer (NSCLC) is the most prevalent form of lung cancer globally, with average age of cancer patients becoming younger gradually. It is of significance to gain a comprehensive understanding of molecular mechanism underlying NSCLC. METHODS: Quantitative polymerase chain reaction (qPCR) and western blot were applied to measure RNA and protein levels separately. Functional assays and western blot were performed to determine the effects of miR-489-3p and USP48 on cell growth, migration and epithelial-mesenchymal transition (EMT) in NSCLC. TOP/FOP flash luciferase reporter assay was carried out to detect the activity of Wnt pathway. Besides, qPCR, RNA pulldown and luciferase reporter assays were conducted to probe into the target gene of miR-489-3p. Immunoprecipitation-western blot (IP-western blot) analysis was implemented to assess the effect of USP48 on the ubiquitination of ß-catenin. RESULTS: miR-489-3p hampers NSCLC cell proliferation, migration and EMT in vitro and NSCLC tumorigenesis and metastasis in vivo. Additionally, miR-489-3p inactivates Wnt/ß-catenin signaling pathway and regulates USP48 to inhibit the ubiquitination of ß-catenin. Moreover, USP48 propels the development of NSCLC cells. CONCLUSIONS: The current study demonstrated that miR-489-3p promotes the malignant progression of NSCLC cells via targeting USP48, which might offer a new perspective into NSCLC treatment.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , MicroARNs , ARN Largo no Codificante , Proteasas Ubiquitina-Específicas , Vía de Señalización Wnt , beta Catenina , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Humanos , Luciferasas/genética , Luciferasas/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , MicroARNs/metabolismo , ARN Largo no Codificante/genética , Proteasas Ubiquitina-Específicas/genética , Proteasas Ubiquitina-Específicas/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
2.
Wei Sheng Wu Xue Bao ; 57(1): 87-96, 2017 Jan 04.
Artículo en Zh | MEDLINE | ID: mdl-29746763

RESUMEN

Objective: In this study, we constructed recombinant Kluyveromyces lactis strains to produce phospholipase C (PLC) of Bacillus cereus. The recombinant enzymes were purified and characterized. Methods: We cloned the PLC encoding gene bcplc of Bacillus cereus. And the amplified fragments were inserted into pKLAC1 to obtain expression plasmids. K. lactis harboring the above plasmids was cultivated to express PLC that was purified by HisTrapTM affinity chromatography and characterized. Results: PLC of B. cereus was cloned and expressed in K. lactis. The recombinant enzyme had shown activity of 19251 U/mg when using p-nitrophenyl phosphorycholine as substrate. Purified PLC exhibited optimum temperature at 80 °C and optimal pH at 9.0. The recombinant enzyme was stable below 40 °C and pH between 7.0 and 8.0. Cu2+ and Co2+ inhibited its activity whereas Zn2+, Mn2+, Ca2+ and Mg2+ stimulated its activity. Conclusion: It is the first time to express and characterize the PLC gene in K. lactis. These research results provide reference for the study of recombinant PLC.


Asunto(s)
Bacillus cereus/enzimología , Proteínas Bacterianas/química , Proteínas Bacterianas/aislamiento & purificación , Expresión Génica , Kluyveromyces/genética , Fosfolipasas de Tipo C/química , Fosfolipasas de Tipo C/aislamiento & purificación , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Clonación Molecular , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Kluyveromyces/metabolismo , Plásmidos/genética , Plásmidos/metabolismo , Temperatura , Fosfolipasas de Tipo C/genética , Fosfolipasas de Tipo C/metabolismo
3.
J Colloid Interface Sci ; 673: 333-345, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38878368

RESUMEN

Ultralight graphene aerogels have gained extensive recognition in the impact protection field. However, attaining both elasticity and durability at low material density is challenging due to their intrinsic conflicts. Inspired by the mantis ootheca, we present a simultaneous improvement in the elasticity, durability, and density restrictions of ultralight graphene aerogels via constructing a multiscale honeycomb microstructure (MHM) within the graphene skeleton. This approach enables resulting graphene aerogel to achieve a strength per unit volume of 284.6 cm3 mg-1, the ability to recover its shape within 10 ms after an impact at 3.569 m/s, and maintain 97.2 % of its sample height after 20,000 cycles at 90 % strain. The operand analyses and calculation results reveal that the MHM structure facilitates this aerogel's dual-stage stress transfer pathway. Initially, the macroscale honeycomb structure (millimeter-scale) of the graphene aerogels bear and transmit stress to the surrounding regions, followed by the microscale honeycomb structure (micron-scale) deformation to convert stress kinetic energy into elastic potential energy. This two-stage stress transition mechanism of the MHM structure can effectively mitigate excessive local stress and suppress strain localization, thus providing remarkable elasticity and durability. Ultimately, the obtained graphene aerogel demonstrates promising applications as a fall height detection device and impact protective material.

4.
Chem Asian J ; 19(11): e202400055, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38545629

RESUMEN

A superelastic self-healing eutectogel was designed and prepared using poly (vinyl alcohol) (PVA) as the bulk skeleton material, while silk fibroin (SF) and two-dimensional (2D) MXene (Ti3C2TX) as reinforcing fillers. In brief, the eutectogel possesses a high tensile strength of 7.63 MPa, and its elongation at break reached 1115.2%, higher than most reported polymers (<1000%). In addition, the eutectogel-assembled sensor has a high ionic conductivity of 0.61 S/m and a high strain sensitivity of 5.17 kPa-1. Moreover, eutectogel shows excellent self-healing ability and can achieve self-healing quickly within 10 min, while its tensile strength and elongation at break can be restored to 84.7% and 97.4% of the initial levels. Besides, a stable electrical signal can be transmitted after 200 cycles at 30% strain. Finally, the eutectogel can withstand various environmental conditions, such as atmospheric or even vacuum evaporation and low-temperature freezing, while maintaining good mechanical and sensing performances. The assembled flexible sensors based on the eutectogel demonstrate their significant application prospects in wearable devices, especially human physiological monitoring.

5.
J Mech Behav Biomed Mater ; 155: 106540, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38615407

RESUMEN

MXene, as a new category of two-dimensional nanomaterials, exhibits a promising prospect in biomedical applications due to its ultrathin structure and morphology, as well as a range of remarkable properties such as biological, chemical, electronic, and optical properties. In this work, different concentrations of MXene (M) were added to polyvinyl alcohol (PVA, P)/nano-hydroxyapatite (n-HA, H) mixed solution, and series of PVA/n-HA/MXene (PHM) composite membranes were obtained by combining sol-gel and freeze-drying processes. Morphology, chemical composition, surface, and mechanical properties of the prepared PHM membranes were characterized by various techniques. Subsequently, the swelling and degradation performances of the composite membranes were tested by swelling and degradation tests. In addition, in vitro studies like cell adhesion, cytotoxicity, proliferation, osteogenic differentiation, and antibacterial properties of MC3T3-E1 were also evaluated. The results showed that the addition of MXene could apparently improve the composite membranes' physicochemical properties, bioactivity, and osteogenic differentiation. Specially, PHM membrane had the best comprehensive properties when the concentration of MXene was set as 2.0% w/v. In a word, the addition of MXene has a positive effect on improving the mechanical properties, osteogenic induction, and antibacterial properties of PH composite membranes, and the prepared PHM composite membranes possess potential applications for guided bone regeneration.


Asunto(s)
Materiales Biocompatibles , Regeneración Ósea , Durapatita , Alcohol Polivinílico , Durapatita/química , Durapatita/farmacología , Alcohol Polivinílico/química , Regeneración Ósea/efectos de los fármacos , Ratones , Animales , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Membranas Artificiales , Fenómenos Mecánicos , Proliferación Celular/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Ensayo de Materiales , Adhesión Celular/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/química , Regeneración Tisular Dirigida , Nanoestructuras/química , Línea Celular , Diferenciación Celular/efectos de los fármacos , Nanocompuestos/química
6.
J Nanosci Nanotechnol ; 12(1): 195-200, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22523965

RESUMEN

The fabrication of polymeric materials with ordered submicron-size void structures is potentially valuable for many applications such as catalysts, separation and adsorbent media. This paper reports the preparation of macroporous protein multilayer films with regular voids using silica nanospheres as templates. Both monodisperse silica colloids and highly ordered assembly silica multilayer films are used as templates to prepare microporous bovine serum albumin multilayer films with ruleless and ordered submicron-sized voids. Glutaraldehyde is used as a crosslinking agent to form a firm net-like protein film on the surface of silica templates. The microporous protein film is obtained after removing of silica templates. Compare with polymer film, protein film has good biocompatibility and biodegradability which will be beneficial to its biological applications.


Asunto(s)
Materiales Biocompatibles Revestidos/síntesis química , Cristalización/métodos , Membranas Artificiales , Impresión Molecular/métodos , Nanoestructuras/química , Nanoestructuras/ultraestructura , Albúmina Sérica Bovina/química , Adsorción , Sustancias Macromoleculares/química , Conformación Molecular , Tamaño de la Partícula , Porosidad , Propiedades de Superficie
7.
Comput Math Methods Med ; 2022: 1301361, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36110570

RESUMEN

To investigate the influences of ultrasonic image-guided erector spinae plane block (ESPB) on postoperative pulmonary air content of lung carcinoma patients undergoing thoracoscopic surgery, 42 patients performed with thoracoscopic radical surgery for lung carcinoma were selected. The patients in the experimental group were performed with ultrasound-guided unilateral ESPB and intravenous general anesthesia. The patients in the control group only underwent intravenous anesthesia. The changes in postoperative pulmonary air content between the two groups were compared. After that, all included patients were divided into the experimental (senior) group (13 cases), the experimental (adult) group (8 cases), the control (senior) group (11 cases), and the control (adult) group (10 cases) according to age. The changes in postoperative pulmonary air content of patients in the four groups were compared. The results showed that lung ultrasound score (LUS) of patients in experimental group was 6.4 ± 3.2 points 0.5 hour after catheter extraction and LUS was 4.1 ± 2.3 points 20 to 30 hours. Both scores were remarkably lower than those of patients in control group (P < 0.05). LUS of lower left anterior area, upper left posterior area, lower left posterior area, upper right posterior area, and lower right posterior area of patients in experimental group was all apparently lower than those in control group 0.5 hour after catheter extraction (P < 0.05). LUS of upper left posterior area, lower left posterior area, lower right anterior area, upper right posterior area, and lower right posterior area of patients in experimental group was all remarkably lower than those in control group 20 to 30 hours after surgery (P < 0.05). LUS of senile patients and middle-aged patients in experimental group 0.5 hour after catheter extraction was 8.01 ± 2.48 points and 5.93 ± 3.91 points, respectively, which were both notably lower than those in control group (P < 0.05). Ultrasound-guided ESPB exerted fewer influences on lung and could effectively improve postoperative pulmonary air content among patients. Hence, it was worthy of clinical promotion.


Asunto(s)
Carcinoma , Neoplasias Pulmonares , Bloqueo Nervioso , Adulto , Humanos , Pulmón/diagnóstico por imagen , Pulmón/cirugía , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/cirugía , Persona de Mediana Edad , Bloqueo Nervioso/métodos , Dolor Postoperatorio/tratamiento farmacológico , Toracoscopía , Ultrasonido , Ultrasonografía Intervencional
8.
J Colloid Interface Sci ; 608(Pt 2): 2158-2168, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34773850

RESUMEN

Binary solvent-based fabrication permits the conductive organohydrogel to function well at low-temperature environments. However, the deep cryogenic and high temperatures are still threatening the performance of conductive organohydrogels in the application of stretchable electronics, biosensors, and intelligent coatings. Here, a radically new method is developed to introduce propylene and carbonate cellulose nanofibrils into freeze tolerance polymer matrix, and fabricate an antifreezing/antiheating organohydrogel integrated a high mechanical strength (1.6 MPa) and high level of ionic conductivity (4.2 S cm-1) over a wide temperature range (-40 to 100 °C). In this designed system, the propylene carbonate with low freezing point and high boiling point was shown to enhance antifreezing (-40 °C) and antiheating (100 °C) performance of organohydrogel. Furthermore, negative charge-rich cellulose nanofibrils (CNFs) were served as an ion transport channel and nanoreinforcements to boost the conductive and mechanical properties of the organohydrogel. In particular, Molecular Dynamics (MD) simulations reveal that propylene carbonate with high dielectric constant is capable of generating ion migration-facilitated effects, enabling the high ionic conductivity of organohydrogel. Tapping into these attributes, potential applications in mechanoresponsive smart coating have been demonstrated utilizing the appealing organohydrogel as a paint, rendering unprecedented protection and monitoring performance.


Asunto(s)
Calor , Hidrogeles , Congelación , Pintura , Temperatura
9.
ACS Appl Mater Interfaces ; 14(35): 40276-40285, 2022 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-36001388

RESUMEN

Sensing materials that are ultrastrong but still superelastic and highly sensitive are crucial for meeting the requirements of future flexible sensors. However, these requirements are challenging to satisfy simultaneously due to the internal constraints among these properties. Here, an ultrastrong and superelastic eutectogel is designed and prepared using a waterborne polyurethane (WPU) network enhanced by two-dimensional (2D) nanosheets in a deep eutectic solvent. The 2D nanosheet-induced noncovalent cross-linking endows the prepared eutectogel with superelasticity and flexibility, and its elongation at break reaches 2071%, higher than those of most polymers (<1000%). Meanwhile, this eutectogel also exhibits a high tensile strength (21.6 MPa), which is strong enough to support 20 000 times its own weight. Such a composite design provides a feasible route for preparing eutectogels with outstanding comprehensive functions without trade-offs among these features. In addition, the eutectogel-assembled sensor possesses a high ionic conductivity of 0.225 S/m and a high strain sensitivity of 1.18 kPa-1. Furthermore, it can be integrated into the sensing arrays for multidimensional signal monitoring without diminishing its pristine strength and flexibility. Surprisingly, the eutectogel can be quickly disintegrated in ethanol due to the WPU's pseudoplastic behavior, providing a competitive way to dispose of waste electronic devices.

10.
Dis Markers ; 2022: 2442094, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35615401

RESUMEN

Both PCAT19 and miR-25-3p have been reported in lung cancer studies, but whether there is a correlation between the two and whether they jointly regulate the progress of lung cancer have not been reported yet. Therefore, this study carried out a further in-depth research. The expression of PCAT19 was detected in lung cancer (LC) tissues and cells by quantitative real-time polymerase chain reaction (qRT-PCR). The effect of PCAT19 on tumor growth was detected in a tumor-bearing model of nude mice. PCAT19-transfected cells were treated with Honokiol and anisomycin. The effects of PCAT19 on proliferation, apoptosis, and cycle of LC cells were investigated by biomolecule experiments. The effects of PCAT19 on the expressions of mitogen-activated protein kinase- (MAPK-) related proteins were evaluated by western blotting. The expression of PCAT19 was decreased in LC tissues and related to patient survival, tumor size, and pathology. In addition, upregulation of PCAT19 hindered LC cell proliferation, miR-25-3p expression, and the activation of extracellular regulated protein kinases (ERK) 1/2, p38, and c-Jun N-terminal kinase (JNK), while facilitating LC cell apoptosis. Furthermore, upregulation of PCAT19 reversed the effects of Honokiol and anisomycin on promoting cell proliferation and inhibiting cell apoptosis. Collectively, our findings show that upregulated PCAT19 suppresses proliferation yet promotes the apoptosis of LC cells through modulating the miR-25-3p/MAP2K4 signaling axis.


Asunto(s)
Neoplasias Pulmonares , MAP Quinasa Quinasa 4 , MicroARNs , ARN Largo no Codificante , Animales , Anisomicina , Apoptosis/genética , Compuestos de Bifenilo , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Lignanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , MAP Quinasa Quinasa 4/metabolismo , Ratones , Ratones Desnudos , MicroARNs/genética , MicroARNs/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo
11.
J Nanosci Nanotechnol ; 11(6): 5068-74, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21770145

RESUMEN

This paper describes a general strategy for grafting protein molecules on silicon surface by using dopamine as adhesive layer. With this method, silicon surface had been successfully modified by BSA monolayer. Fourier transform infrared spectra, X-ray photoelectron spectroscopy, contact angle analysis and atomic force microscopy confirmed the sequential grafting of initiator and protein molecules. Cell adhesion experiments with PC-12 cells showed that the obtained monolayer exhibits good biocompatibility. The corrosion resistance behavior of the polydopamine and BSA modified silicon wafers was investigated by potentiodynamic test, which indicated that the modified surfaces exhibited a better anti-corrosion capability than silicon surface. All these results must be valuable for the application of protein monolayer in biological and biomedical technology.


Asunto(s)
Materiales Biocompatibles/química , Nanotecnología/métodos , Albúmina Sérica Bovina/química , Silicio/química , Animales , Biotecnología/métodos , Bovinos , Adhesión Celular , Línea Celular Tumoral , Supervivencia Celular , Dopamina/química , Dopamina/metabolismo , Ensayo de Materiales , Microscopía de Fuerza Atómica , Microscopía Fluorescente , Ratas , Albúmina Sérica Bovina/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier
12.
ACS Appl Mater Interfaces ; 13(22): 26352-26361, 2021 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-34033482

RESUMEN

Extremely low density carbon nanotubes/graphene hybrid aerogels (CNG) are highly potential active materials for fabricating flexible devices, owing to synergistic effects with one (nanotubes) and two (graphene) dimensional characters in a single structure. However, conquering the long-standing dilemma among low electronic conductivity and inferior mechanical properties for CNG remains a challenging task. Here, an ultralight CNG aerogel (1.52 mg cm-3) with prominent electronic conductivity and mechanical resilience is facilely fabricated through a triple roles design of the sodium dodecyl sulfate (SDS), namely anchoring metal ions, dispersing carbon nanotubes, and inducing self-assembly. It is demonstrated that the Ba2+ can be effectively anchored into the GO interlayers by coupling it with the SDS to reinforce the intersheet interactions, thereby achieving remarkable improvement in mechanical properties (Young's moduli up to 18.3 kPa). Density functional theory calculations reveal that the anchored Ba2+ acting as molecular bridges can availably reduce the tunneling barrier between the GO sheets and facilitate the multidirectional and fast transport of electronics, inducing the high electrical conductivity of CNG (12.55 S cm-1). Taking advantage of these features, potential applications in flexible sensing devices have been demonstrated utilizing the remarkable CNG as an active material, giving extraordinary sensing performance including high sensitivity (48.6 kPa-1), ultralow detection limit (10 Pa), and ultrafast response (18 ms).

13.
Mater Sci Eng C Mater Biol Appl ; 126: 112171, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34082972

RESUMEN

The lack of antibacterial properties limits the application of bacterial cellulose hydrogels in wound dressings. To overcome this deficiency, silver nanoparticles (AgNPs) were introduced as antibacterial agents into a polyvinyl alcohol (PVA)/bacterial cellulose (BC) solution. A freeze-thaw method promoted formation of PVA/BC/Ag hydrogels and improved their mechanical properties. The physicochemical and biological properties of this hydrogel were systematically characterized. Those results showed the hydrogels contained a porous three-dimensional reticulum structure and had high mechanical properties. Also, the hydrogels possessed outstanding antibacterial properties and good biocompatibilities. More importantly, it effectively repaired wound defects in mice models and wound healing reached 97.89% within 15 days, and far exceeded other groups and indicated its potential for use in wound treatment applications.


Asunto(s)
Nanopartículas del Metal , Alcohol Polivinílico , Animales , Antibacterianos/farmacología , Celulosa/farmacología , Hidrogeles/farmacología , Ratones , Plata/farmacología , Cicatrización de Heridas
14.
Front Oncol ; 11: 595609, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33777742

RESUMEN

BACKGROUND: The effects of up-regulated CircCHST15 on lung cancer remained unclear. In this study, the role of CircCHST15 in lung cancer was investigated. METHODS: Dual-luciferase reporter verified the bioinformatics prediction that CircCHST15 targeted miR-155-5p and miR-194-5p. The correlation between CircCHST15 and PD-L1 was analyzed by Pearson analysis. CCK-8 and colony formation was performed to determine the viability and proliferation of lung cancer cells. After the lung cancer (subcutaneous-xenotransplant) model was established in mice, the T cell subtype and related cytokines in mouse tumor tissues were detected by flow cytometry and ELISA. Moreover, the expressions of CircCHST15, miR-155-5p, miR-194-5p, immune-related, and proliferation-related factors of the lung cancer cells or mice tumor tissues were detected by immunohistochemistry, RT-qPCR, or Western blot. RESULTS: CircCHST15 and PD-L1 were high-expressed in lung cancer, and the two was positively correlated. CircCHST15 targeted miR-155-5p and miR-194-5p, the later further targeted PD-L1. Lung cancer cell viability and proliferation were increased by miR-155-5p and inhibited by miR-194-5p. CircCHST15 located in the cytoplasm promoted tumor growth, down-regulated the expressions of miR-155-5p and miR-194-5p, and up-regulated the expressions of PD-L1, Ki-67, PCNA, CCL17, CCL22, IFN-γ, TNF-ß, and IL-10. Also, CircCHST15 decreased the CD8+ cells in mouse blood and tumor, but increased the Tregs in mouse tumor. PD-L1 inhibitor showed an opposite effect to CircCHST15 on mouse tumors. CONCLUSION: CircCHST15 sponged miR-155-5p and miR-194-5p to promote the PD-L1-mediated immune escape of lung cancer cells.

15.
Int J Biol Macromol ; 183: 2326-2336, 2021 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-34089760

RESUMEN

In this study, a water-soluble bacterial cellulose sulfate (BCS) was prepared with sulfur trioxide pyridine complex (SO3· Py) in a lithium chloride (LiCl)/dimethylacetamide (DMAc) homogeneous solution system using bacterial cellulose (BC). The structural study showed that the value for the degrees of substitution of BCS was 1.23. After modification, the C-6 hydroxyl group of BC was completely substituted and the C-2 and C-3 hydroxyl groups were partially substituted. In an aqueous solution, the BCS existed as a linear polymer with irregular coil conformation, which was consistent with the findings observed using atomic force microscopy. The steady-state shear flow and dynamic viscoelasticity were systematically determined over a range of BCS concentrations (1 %-4 %, w/v) and temperature (5 °C-50 °C). Steady-state flow experiments revealed that BCS exhibited shear thinning behavior, which increased with an increase in concentration and a decrease in temperature. These observations were quantitatively demonstrated using the cross model. Moreover, based on the dynamical viscoelastic properties, we confirmed that BCS was a temperature-sensitive and weak elastic gel, which was somewhere between a dilute solution and an elastic gel. Therefore, considering the special synthetic strategy and rheological behavior, BCS might be used as a renewable material in the field of biological tissue engineering, especially in the manufacture of injectable hydrogels, cell scaffolds, and as a drug carrier.


Asunto(s)
Celulosa/análogos & derivados , Gluconacetobacter xylinus/metabolismo , Conformación de Carbohidratos , Celulosa/química , Celulosa/aislamiento & purificación , Portadores de Fármacos , Elasticidad , Geles , Reología , Temperatura , Andamios del Tejido , Viscosidad
16.
Langmuir ; 26(20): 15830-6, 2010 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-20873824

RESUMEN

Reduced graphene oxide (RGO) sheets were covalently assembled onto silicon wafers via a multistep route based on the chemical adsorption and thermal reduction of graphene oxide (GO). The formation and microstructure of RGO were analyzed by X-ray photoelectron spectroscopy (XPS), attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, Raman spectroscopy, and water contact angle (WCA) measurements. Characterization by atomic force microscopy (AFM) was performed to evaluate the morphology and microtribological behaviors of the samples. Macrotribological performance was tested on a ball-on-plate tribometer. Results show that the assembled RGO possesses good friction reduction and antiwear ability, properties ascribed to its intrinsic structure, that is, the covalent bonding to the substrate and self-lubricating property of RGO.

17.
J Nanosci Nanotechnol ; 10(2): 933-40, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20352739

RESUMEN

At the room temperature, a novel and environmental friendly approach for synthesizing polyaniline (PANI) nanofibers on a large scale is presented firstly in the aqueous phase by ultraviolet (UV)-assisted polymerization using cetyltrimethylammonium bromide (CTAB) as the "soft-template." It is obvious that the polymerization process can be accelerated under the illumination of UV light and the preliminary mechanism has been pointed out. Furthermore, it also can be noted that the lower concentrations of CTAB and HCl are helpful for the fabrication of smooth and uniform PANI nanofibers. As observed with FE-SEM and TEM, the as-synthesized PANI nanostructures under the appropriate conditions are composed of uniform nanofibers with the average diameter of about 100 nm and the length of several micrometers. Subsequently, the synthesized PANI nanostructures are characterized with UV-vis, FT-IR, XRD spectra, and the typical physical and chemical properties of PANI are displayed. In addition, the conductivity of the synthesized PANI nanofibers was also measured with the four probe method and the excellent conductivity was presented. In summary, the procedure presented here only involving exposure of an acidic aqueous solution of aniline to UV light illumination is so simple and the needed equipment is so low cost, from the viewpoint of technological applications, that the large-scale UV-assisted polymerization of PANI nanofibers from the monomer solution is feasible and promising.

18.
J Colloid Interface Sci ; 559: 152-161, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-31622817

RESUMEN

Mechanically tough polymers with excellent room temperature self-healing capacity have aroused strong interest in soft electronics, electronic skins and flexible energy storage devices. However, achieving such polymers remains a challenge due to tardy diffusion dynamics. Herein, a robust and readily self-healing polymer, which is synthesized by one-pot polymerization among 2,4'-tolylene diisocyanate, isophorone diisocyanate, and poly(oxy-1,4-butanediyl), is achieved through reasonably tuning the hardness of the molecular segment and the strength of the dynamic crosslinking bond. The poly(oxy-1,4-butanediyl) that act as a soft segment can effectively avoid the microphase separation, enabling rapid chain mobility of the polymer at the room temperature. Furthermore, the dual H-bonding from 2,4'-tolylene diisocyanate segment acting as a relatively strong crosslinking bond contributes to high mechanical strength, while the weaker single H-bonding from isophorone diisocyanate segment can efficiently dissipate strain energy by bond rupture, endowing the polymer with rapid room temperature self-healing ability. Featuring state-of-the-art of robust stress strength (≈1.3 MPa), high self-healing efficiency (97% within 6 h), and large tensile strain (≈2100%), the resulting polymers are used for the fabrication of stretchable and self-healable electrical sensor, which can be employed to monitor a variety of physiological activities in real time. The described strategy is promising and universal for healable materials, displaying great potential for developing soft electronics.

19.
Materials (Basel) ; 13(17)2020 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-32825694

RESUMEN

Removing heavy metal ions from industrial wastewater is one of the most important and difficult areas of the water treatment industry. In this study, Bacterial Cellulose/Polyvinyl Alcohol/Graphene Oxide/Attapulgite (BC/PVA/GO/APT) composites were successfully prepared via a repeated freeze-thaw method using bacterial cellulose, polyvinyl alcohol as the skeleton, and graphene oxide, attapulgite as fillers. The capacities of adsorbing Cu2+ and Pb2+ ions in solution were investigated. FTIR, XRD, SEM, BET, and TG-DSC analyses showed that the BC/PVA/GO/APT hydrogel has a better hydrophilicity, a larger specific surface area and a better thermal stability than traditional materials. We found that the adsorption of Cu2+ and Pb2+ ions can be accurately predicted by the Freundlich kinetic model, and the optimal adsorption capacities of these ions were found to be 150.79 mg/g and 217.8 mg/g respectively. Thermodynamic results showed that the adsorption process is spontaneous and exothermic. BC/PVA/GO/APT composites are suggested to be an ideal adsorption material for removing heavy metal ions from industrial wastewater.

20.
Cell Signal ; 74: 109693, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32599139

RESUMEN

Non-small-cell lung cancer (NSCLC) is one of the most common solid tumors and the leading cause of lung cancer-related fatality. Growing evidence has indicated that circular RNAs (circRNAs) play important roles in the progression of multiple human cancers. As a novel circRNA, very little research has focused on the function of circRNA TUBA1C (circTUBA1C) in cancer development, including NSCLC. In the present study, we found that the expression of circTUBA1C was significantly upregulated in NSCLC tissues. The loss-of function assays suggested that circTUBA1C deficiency notably hampered cell proliferation as well as accelerated cell apoptosis in NSCLC. In mechanism, we discovered that circTUBA1C could act as a sponge for miR-143-3p and then negatively regulate miR-143-3p. Moreover, rescue assays demonstrated that knockdown of miR-143-3p could reverse circTUBA1C silence-mediated effects on cell proliferation and apoptosis. Besides, we established a xenografted tumor model to investigate the function of circTUBA1C in vivo. The result illustrated that the decline of tumor growth resulted from circTUBA1C deficiency could be recovered by miR-143-3p knockdown. Taken together, these findings indicated the important role of circTUBA1C/miR-143-3p axis in NSCLC, which may provide a potential target for NSCLC therapy.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Neoplasias Pulmonares/metabolismo , MicroARNs/fisiología , ARN Circular/fisiología , Células A549 , Animales , Biomarcadores de Tumor , Proteínas del Citoesqueleto/genética , Humanos , Ratones , Ratones Endogámicos BALB C
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