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1.
Micromachines (Basel) ; 14(8)2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37630094

RESUMEN

An improper Z-increment in laser solid forming can result in fluctuations in the off-focus amount during the manufacturing procedure, thereby exerting an influence on the precision and quality of the fabricated component. To solve this problem, this study proposes a closed-loop control system for a Z-increment based on machine vision monitoring. Real-time monitoring of the precise cladding height is accomplished by constructing a paraxial monitoring system, utilizing edge detection technology and an inverse perspective transformation model. This system enables the continuous assessment of the cladding height, which serves as a control signal for the regulation of the Z-increments in real-time. This ensures the maintenance of a constant off-focus amount throughout the manufacturing process. The experimental findings indicate that the proposed approach yields a maximum relative error of 1.664% in determining the cladding layer height, thereby enabling accurate detection of this parameter. Moreover, the real-time adjustment of the Z-increment quantities results in reduced standard deviations of individual cladding layer heights, and the height of the cladding layer increases. This proactive adjustment significantly enhances the stability of the manufacturing process and improves the utilization of powder material. This study can, therefore, provide effective guidance for process control and product optimization in laser solid forming.

2.
Int J Biol Macromol ; 246: 125667, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37406908

RESUMEN

Flexible and stretchable substrates based on pure natural polymers have attracted widespread attention for next-generation "green" electronics. However, fabrication of stretchable and "green" electronic sensors with integrated high stretchability, optical transmittance and good conductivity still remains tremendous challenges. Herein, alginate ionic gel films (AIGFs) with integrated high stretchability (tensile strength of 4.13 MPa and 191.1 % fracture strain) and excellent transparent properties (transparency of ∼92 %) are achieved by the glycerol inducing physical crosslinking and CaCl2 initiating ionic crosslinking, a simple soaking and drying strategy. The obtained gel films not only exhibit good ionic conductivity, but also high reliability, wide-range sensing, and multiple sensitivity to external stimulus. More importantly, these ionic conductive gel films as green substrates are successfully utilized for construction of flexible and patterned optoelectronic devices. This promising strategy will open up new powerful routes to construct highly stretchable, transparent, and ionic conductive substrates for multifunctional sensors and devices.


Asunto(s)
Electrónica , Polímeros , Reproducibilidad de los Resultados , Polímeros/química , Iones , Resistencia a la Tracción
3.
Int J Biol Macromol ; 246: 125683, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37419262

RESUMEN

Ionic conductive hydrogel fibers based on natural polymers provide an immense focus for a new generation of electronics due to their flexibility and knittability. The feasibility of utilizing pure natural polymer-based hydrogel fibers could be drastically improved if their mechanical and transparent performances satisfy the requirements of actual practice. Herein, we report a facile fabrication strategy for significantly stretchable and sensitive sodium alginate ionic hydrogel fibers (SAIFs), by glycerol initiating physical crosslinking and by CaCl2 inducing ionic crosslinking. The obtained ionic hydrogel fibers not only show significant stretchability (tensile strength of 1.55 MPa and fracture strain of ∼161 %), but also exhibit wide-range sensing, satisfactorily stable, rapidly responsive, and multiply sensitive abilities to external stimulus. In addition, the ionic hydrogel fibers have excellent transparency (over 90 % in a wide wavelength range), and good anti-evaporation and anti-freezing properties. Furthermore, the SAIFs have been easily knitted into a textile, and successfully applied as wearable sensors to recognize human motions, by observing the output electrical signals. Our methodology for fabrication intelligent SAIFs will shed light on artificial flexible electronics and other textile-based strain sensors.


Asunto(s)
Hidrogeles , Polímeros , Humanos , Conductividad Eléctrica , Iones , Resistencia a la Tracción
4.
Food Sci Nutr ; 11(4): 1728-1735, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37051352

RESUMEN

Perillae Fructus oil has an important function in relieving cold stress. However, its application in this aspect has still been restricted because of instability and low bioavailability. In this study, Perillae Fructus oil was extracted through Soxhlet extraction, analyzed through gas chromatography-mass spectrometry (GC-MS), and nanopackaged into a yeast shell for the preparation of nanoparticles for oral administration. The characteristics of the nanoparticles were investigated using a Malvern zeta-size nanoinstrument, scanning electron microscopy (SEM), and high-performance liquid chromatography (HPLC). Then, the roles of orally administered nanoparticles in relieving cold stress were evaluated by investigating blood physiological and biochemical indexes in mice. The results showed that the oil yield from Perillae Fructus and shell yield from yeast cells were ~48.37% and ~16.87%, respectively. Approximately 89.21% of the added oil was packaged into the yeast shell to form nanoparticles with an average diameter of 316.74 nm and a surface charge of +2.9 mV. The nanoparticles were stable in simulated gastric acid and could be effectively released in simulated intestinal fluid with an efficiency of ~91.34%. After oral administration of nanoparticles, the mouse blood indexes of white blood cells (WBCs), superoxide dismutase (SOD) activity, and malonaldehyde (MDA) content were recovered compared to those in model mice, with a more remarkable effect than oral administration of free Perillae Fructus oil. Overall, the stability and bioavailability were improved by packaging Perillae Fructus oil into a yeast shell. These nanoparticles are a new agent for the prevention of cold stress.

5.
Reprod Biol ; 23(1): 100731, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36634519

RESUMEN

The multifunctional molecule chondroitin sulfate proteoglycan 4 (CSPG4/NG2) plays key roles in organogenesis and tumorigenesis. However, its roles in placentation remain unclear. In this study, CSPG4 expression in human and mouse placentas was investigated through immunohistochemistry (IHC), qPCR and western blotting. The theoretical structure and function of CSPG4 were assessed using bioinformatic tools, and the functions of CSPG4 in fetal and placental development were investigated using a mouse model established by trophoblast-specific CSPG4 knockdown and a trophoblast cell line with CSPG4 knockout by lentivirus infection. The results showed that CSPG4 was mainly located in trophoblasts in both human placentas and mouse placentas, with a higher level in preeclampsia (PE) placentas than in healthy control placentas. Furthermore, there was a trend of increasing expression in mouse placentas during pregnancy. The 3D structure of CSPG4 was visualized using an M model composed of two chains, and the structure implied that CSPG4 was a multifunctional molecule containing multiple pockets with multiligand binding sites and enzyme active sites. Trophoblast-specific CSPG4 knockdown caused frequent fetal loss, and viable fetal development was restricted by poor placentation, with mice placentas having reduced weight and width. The proliferation and invasion of CSPG4-knockout trophoblasts were significantly inhibited, and as such, the molecular signaling of AKT and ERK phosphorylation was inhibited, and the expression of MMP2 and MMP9 was reduced. In summary, CSPG4 deficiency inhibited trophoblast proliferation and invasion, which was associated with AKT, ERK and MMP signaling. CSPG4 deficiency also caused pregnancy complications with poor placentation in mice.


Asunto(s)
Placentación , Preeclampsia , Animales , Femenino , Humanos , Ratones , Embarazo , Movimiento Celular , Proteoglicanos Tipo Condroitín Sulfato/metabolismo , Modelos Animales de Enfermedad , Proteínas de la Membrana/metabolismo , Placenta/metabolismo , Preeclampsia/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Trofoblastos/metabolismo
6.
Molecules ; 29(1)2023 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-38202802

RESUMEN

Understanding the pyrolysis product distributions of deep eutectic solvent (DES)-isolated lignins (DESLs) from different types of biomass is of great significance for lignin valorization. The structure and pyrolysis properties of DESLs obtained from eucalyptus (E-DESL), pine (P-DESL), and rice straw (R-DESL) were studied through the use of various methods such as elemental analysis, GPC, HS-GC, and NMR techniques, and the pyrolysis characteristics and product distributions of the DESLs were also further investigated through the use of TGA, Py-GC/MS, and tubular furnace pyrolysis. DESLs with high purity (88.5-92.7%) can be efficiently separated from biomass while cellulose is retained. E-DESL has a relatively low molecular weight, and P-DESL has a relatively higher hydrogen-carbon effective ratio and a lower number of condensation structures. The Py-GC/MS results show that, during DESL pyrolysis, the monomeric aromatic hydrocarbons, p-hydroxyphenyl-type phenols, and catechol-type phenols are gradually released when the guaiacyl-type phenols and syringyl-type phenols decrease with the rising temperature. 4-methylguaiacol and 4-methylcatechol, derived from the guaiacyl-type structural units, are positively correlated with temperature, which causes a significant increase in products with a side-chain carbon number of 1 from P-DESL pyrolysis. 4-vinylphenol, as a representative product of the R-DESL, derived from p-hydroxyphenyl-type structural units, also gradually increased. In addition, the P-DESL produces more bio-oil during pyrolysis, while gases have the highest distribution in E-DESL pyrolysis. It is of great significance to study the characteristic product distribution of lignin isolated through the use of DES for lignin directional conversion into specific high-value aromatic compounds.


Asunto(s)
Eucalyptus , Oryza , Pinus , Lignina , Disolventes Eutécticos Profundos , Pirólisis , Fenoles , Carbono
7.
Micromachines (Basel) ; 13(10)2022 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-36296076

RESUMEN

The development of pressure sensors of high sensitivity and stable robustness over a broad range is indispensable for the future progress of electronic skin applicable to the detection of normal and shear pressures of various dynamic human motions. Herein, we present a flexible capacitive tactile sensing array that incorporates a porous dielectric layer with micro-patterned structures on the surface to enable the sensitive detection of normal and shear pressures. The proposed sensing array showed great pressure-sensing performance in the experiments, with a broad sensing range from several kPa to 150 kPa of normal pressure and 20 kPa of shear pressure. Sensitivities of 0.54%/kPa at 10 kPa and below, 0.45%/kPa between 10 kPa and 80 kPa, and 0.12%/kPa at 80 kPa and above were achieved for normal pressures. Meanwhile, for shear pressures, sensitivities up to 1.14%/kPa and 1.08%/kPa in x and y directions, respectively, and below 10 kPa, 0.73%/kPa, and 0.75%/kPa under shear pressure over 10 kPa were also validated. The performance of the finger-attached sensing array was also demonstrated, demonstrating which was a potential electronic skin to use in all kinds of wearable devices, including prosthetic hands, surgical robots, and other pressure monitoring systems.

8.
Int J Biol Macromol ; 220: 766-774, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-35987360

RESUMEN

Polyvinylidene fluoride (PVDF) is commonly used in the chemical, electronic, and petrochemical industries because of its chemical and physical attributes. This study aimed to make novel PVDF-based composite with a high loading of silanized wood powder and micro/nanocellulose fibers, where glycerol acts as both a dispersant and a plasticizer all-in-one composite application for the first time. The purpose was also extended to systematically investigate their mechanical properties and melt flow. Results have demonstrated the efficiency of utilizing the cellulose fibers in bio-composites. With the addition of 30 wt% of filling materials, When the content of silanized cellulose fibers in glycerol dispersion is 25 wt%, the flexural strength and tensile strength reach the maximum value 72.30 MPa and 52.28 MPa. The experimental results indicate that silanized micro/nanocellulose fiber-reinforced PVDF/wood composites are a promising composite formula to help improve performance and reduce costs. It is an excellent example of utilizing biomass resources as a renewable/recyclable, sustainable and low-cost material to reduce the use of petroleum-based polymer, and improve the mechanical properties of composites.


Asunto(s)
Petróleo , Madera , Celulosa/química , Polímeros de Fluorocarbono , Glicerol/análisis , Ensayo de Materiales , Petróleo/análisis , Plastificantes , Polímeros/química , Polivinilos , Polvos , Madera/química
9.
Materials (Basel) ; 15(13)2022 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-35806526

RESUMEN

The spills of crude oil and other organic chemicals are common around the world, resulting in severe damage to the environment and ecosystem. Therefore, developing low-cost and eco-friendly absorption material is in urgent need. In this study, we report a superhydrophobic and oleophilic porous material using biomass cuttlebone as the scaffold. A layer of polydopamine is grafted on the cuttlebone as the adhesion layer between the cuttlebone and the superhydrophobic coating. The in situ grown silica micro/nanoparticles on top of the adhesion layer provide the anchoring spots for grafting the fluorinated hydrocarbon and a rough topography for realizing superhydrophobicity. The static water contact angle of the superhydrophobic cuttlebone reaches 152°, and its oil contact angle is ~0°. The excellent oil-water separation efficiency of the prepared superhydrophobic cuttlebone is demonstrated using high-density oil/water mixtures and low-density oil/water mixtures.

10.
Oncol Lett ; 21(1): 18, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33240424

RESUMEN

Glioblastoma multiforme (GBM) has a poor prognosis and its recurrence and mortality rates are high. At present, there is no effective clinical method to control its progression and recurrence. Traditional Chinese Medicine has a high status not only in China, but also in the world. Certain drugs are also used in the clinical treatment of tumor diseases. In clinical practice, Huang-Lian-Tang (HLT) has proven efficacy in treating brain diseases and preventing tumor recurrence. However, the mechanisms of action have remained elusive. The present study explored the potential mechanisms of HLT in the treatment of gliomas based on network pharmacology. First, information on the composition of HLT was obtained from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform, and the composition and targets of the chemical substances contained in the herbs were analyzed. Subsequently, a pharmacological interaction network for HLT was built. Furthermore, the expressed genes of patients with GBM were obtained from Gene Expression Omnibus database and screened. A protein-protein interaction network was then constructed for both sets of data and they were combined with a topology method for analysis. Finally, the screened genes were subjected to enrichment analysis and pathway analysis. A total of 386 candidate targets and 7 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were screened, which were mainly associated with amino acid metabolism. Gene Ontology enrichment analysis and KEGG signal pathway analysis indicated that these targets are involved in anti-apoptosis, anti-oxidative stress, multicellular biological processes and other physiological and pathological processes related to the occurrence and development of GBM. In conclusion, the present results indicated that the mechanisms of action of HLT against GBM involve multiple targets and signaling pathways that are related to tumorigenesis and progression. The present study not only provided a novel theoretical basis for Traditional Chinese Medicine to treat tumors but also novel ideas for the treatment of GBM.

11.
Reprod Domest Anim ; 55(11): 1479-1489, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32762098

RESUMEN

Non-infectious prenatal mortality severely affects the porcine industry, with pathological placentation as a likely key reason. Previous studies have demonstrated that peroxisome proliferator-activated receptor gamma (PPARγ) deficiency causes defects in the uteroplacental vasculature and induces embryonic losses in mice. However, its role in porcine placental angiogenesis remains unclear. In the present study, PPARγ expression was investigated in porcine uteroplacental tissues at gestational day (GD) 25, GD40 and GD70 via quantitative polymerase chain reaction (qPCR), Western blot and immunohistochemistry (IHC). Moreover, the roles of PPARγ in porcine placental angiogenesis were investigated using a cell model of porcine umbilical vein endothelial cells (PUVECs) to conduct proliferation, migration and tube formation assays in vitro and a mouse xenograft model to assess capillary formation in vivo. The results showed that PPARγ was mainly located in the glandular epithelium, trophoblast, amniotic chorion epithelium and vascular endothelium, as indicated by the higher expression levels at GD25 and GD40 than at GD70 in endometrium and by higher expression levels at GD40 and GD70 than at GD25 in placenta. Moreover, PPARγ expression was significantly downregulated in placenta with dead foetus. In PUVECs, knocking out PPARγ significantly inhibited proliferation, migration and tube formation in vitro and inhibited capillary formation in mouse xenografts in vivo by blocking S-phase, promoting apoptosis and downregulating the angiogenic factors of VEGF and its receptors. Overall, the spatiotemporal heterogeneity of PPARγ expression in porcine uteroplacental tissue suggests its vital role in endometrial remodelling and placental angiogenesis, and PPARγ regulates placental angiogenesis through VEGF-mediated signalling.


Asunto(s)
PPAR gamma/metabolismo , Placenta/irrigación sanguínea , Sus scrofa/fisiología , Animales , Capilares/crecimiento & desarrollo , Línea Celular , Femenino , Xenoinjertos , Ratones Endogámicos C57BL , Neovascularización Fisiológica , PPAR gamma/genética , Placenta/metabolismo , Embarazo , Transducción de Señal , Útero/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo
12.
Carbohydr Polym ; 247: 116694, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-32829822

RESUMEN

In this study, nanocellulose/nanochitin membranes were prepared by suction filtrating 2,2,6,6-tetramethylpiperidine-1-oxyl-oxidized cellulose nanofiber (TOCNF)/partially deacetylated α-chitin nanofiber (α-DECHN) mixed suspensions. The result shows that, with a 1:1 ratio of nanocellulose to nanochitin, the tensile strength of the obtained composite membrane reaches 115.7 MPa and its light transmittance is 77.6 %. Heptadecafluoro-1,1,2,2-tetrahydrodecyl dimethylchlorosilane (HFTD) modified nano SiO2 (F-SiO2), was utilized to construct rough micro/nanostructures on the surfaces of the composite membranes by screen printing, forming high-strength, transparent and superhydrophobic nanocellulose/nanochitin membranes. Atomic force microscope (AFM) images reveal that nanocellulose and nanochitin, with the width between 5 nm and 20 nm and the length between 400 nm and 1.1 µm, are crosslinked with each other. The superhydrophobic nanocellulose/nanochitin composite membranes functionalized with a 2.0 wt% F-SiO2 suspension has a few clusters on its surface. The contact angle of this membrane is 150.1°, and its light transmittance is 70.4 %.

13.
Ann Transl Med ; 8(7): 453, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32395497

RESUMEN

BACKGROUND: Breast cancer (BC) is one of the most common cancers with high mortality worldwide. In the present study, through bioinformatics analysis, we aimed to identify new biomarkers to predict the survival rate of BC patients. METHODS: Differentially expressed genes (DEGs) between low- and high-tumor mutation burden (TMB) groups were identified by using The Cancer Genome Atlas (TCGA) dataset and integrated analysis. Gene Ontology (GO), Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis, and the protein-protein interaction (PPI) network, were applied to predict the function of these above DEGs. Then, the Cox proportional hazard model was developed to screen DEGs. Based on the prognostic signature, survival analysis was used on The Cancer Genome Atlas Breast Invasive Carcinoma (TCGA-BRCA) dataset. Finally, the single-sample gene set enrichment (ssGSEA) analysis was employed to estimate immune cells related to this signature. RESULTS: To create a prognostic signature, 6 DEGs were identified. The results revealed that the survival time of patients with high-risk scores based on the expression of the six-gene signature was dramatically shorter than that of patients with low-risk scores in BC. Furthermore, survival analysis and multivariate cox analysis indicated that the six-gene signature was an independent prognostic factor of BC. Then, we built a nomogram that integrated the clinicopathological factors with the six-gene signature to predict the survival probability of BC patients. We eventually predicted the 20 most vital small molecule drugs by CMap, and Nadolol was considered as the most promising small molecule to treat BC. Moreover, ssGSEA analysis showed that the 6 genes were closely associated with immune cells. CONCLUSIONS: We constructed a six-gene signature associated with TMB that can improve the prognosis prediction and could be seen as a biomarker for BC patients.

14.
J Cell Mol Med ; 24(8): 4830-4838, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32160650

RESUMEN

Nowadays, research on CSCs is still in an initial stage, and there are few studies reporting the successful isolation and identification of CSCs. In the present study, we attempted to isolate CSCs through cultivating the cell line MKN45 in defined serum-free medium and study the expression of stem cell markers or related proteins (Oct3/4, Sox2, Nanog and CD44) in CSCs. Moreover, immunofluorescence staining was performed to validate the stem cell markers of spheroid body-forming cells. Further experiments were used to evaluate the SPOP expression in tumorsphere cells. In addition, ADAMTS9-AS2 is a lncRNA that contributes to the genesis and development of many cancers, including gastric cancer (GC). We found ADAMTS9-AS2 functioned as an anti-oncogene and positively correlated with the expression of SPOP in GC tissues by combining bioinformatics analyses. Furthermore, we reported that ADAMTS9-AS2 regulated the expression of SPOP in GC cells and tumorsphere cells to inhibit GC progression. Together, our results demonstrated that SPOP and ADAMTS9-AS2 can be potential targets for GC treatment.


Asunto(s)
Proliferación Celular/genética , Proteínas Nucleares/genética , ARN Largo no Codificante/genética , Proteínas Represoras/genética , Neoplasias Gástricas/genética , Animales , Pruebas de Carcinogenicidad , Línea Celular Tumoral , Movimiento Celular/genética , Regulación Neoplásica de la Expresión Génica/genética , Xenoinjertos , Humanos , Ratones , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Transducción de Señal/genética , Neoplasias Gástricas/patología
15.
Int J Biol Macromol ; 156: 1183-1190, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-31756476

RESUMEN

In this study, a series of conductive composite wires were successfully prepared by combining dispersions of multi-wall carbon nanotubes (MWCNTs) and TEMPO-oxidized cellulose nanofibers (TOCNFs) with different MWCNTs contents into a dispersion of partially deacetylated α-chitin nanofibers (α-DECHNs) followed with a drying process. The TOCNFs/MWCNTs/α-DECHNs composite wires were prepared by extruding the negatively charged TOCNFs/MWCNTs dispersion into the positively charged α-DECHNs dispersion. The contact of the positively charged α-DECHNs and the negatively charged TOCNFs/MWCNTs triggers the electrostatic interaction (heterocoagulation) resulting in wire-shaped conductive composites. The SEM analysis indicates this conductive composite material has a wire-like shape with a rough but tight surface. The properties of samples were characterized by a zeta potential analyzer (Zetasizer Nano), a four-probe, an electrochemical workstation, a Fourier transform infrared spectroscopy (FTIR), an X-ray diffractometer (XRD), and a thermogravimetric analyzer (TG). Besides, the conductivity and the AC impedance of TOCNFs/MWCNTs/α-DECHNs composite wires with different MWCNTs contents were also analyzed. The conductivity of the composite wire increases from 9.98 × 10-6 S∙cm-1 to 1.56 × 10-3 S∙cm-1 as the MWCNTs content raises from 3.0 wt% to 14.0 wt%. When the MWCNTs content reaches 14.0 wt%, the prepared composite wire can light up LED at a voltage of 5 V, indicating the great potential of this biomass-based conductive composite in conductive material application.


Asunto(s)
Aniones/química , Biomasa , Cationes/química , Celulosa/química , Quitina/química , Nanocables , Nanocables/ultraestructura , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría
16.
Carbohydr Polym ; 225: 115229, 2019 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-31521295

RESUMEN

Nanopaper prepared from cellulose nanofibers (CNFs) is a kind of promising substrate for various high-tech devices. However, several drawbacks including poor water stability and weak corrosion resistance still remain, which limit the practical applications of the nanopaper. Herein, we present a simple and low-cost method for fabricating transparent and superhydrophobic nanopaper by spraying fluorinated silica/multi-walled carbon nanotubes (SiO2/MWCNTs) composite on the nanopaper. A series of functional nanopaper were fabricated, which shows excellent performance of water repellency, chemical stability, conductivity, thermostability and self-cleaning property. Among them, the nanopaper modified with the composite containing 0.5 wt% MWCNTs has a water contact angle of about 163°, transparency of 79.96% and the sheet resistance of 3.15 × 106 Ω sq-1. The combination of the promising features in a material offers attractive prospects, and enables our nanopaper could be tailored for emerging applications such as flexible electronics, display protection and intelligent packages.

17.
Int J Biol Macromol ; 131: 336-342, 2019 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-30840865

RESUMEN

A series of highly porous and biocompatible poly (vinyl alcohol) (PVA) hydrogels containing partially deacetylated α-chitin nanowhiskers (ChWs) were fabricated by the double-cross-link (DC) with glutaraldehyde (GA) and repeating freeze-thawing cycle. Then these hydrogels were used as carrier for bovine serum albumin (BSA), which served as the model drug. The nanowhiskers worked effectively to raise the mechanical property of the PVA/ChWs hydrogels. This property increased significantly from 1.55 to 26.59 MPa with the increase of the ratio of ChWs to PVA from 0% to 40%. Additionally, the morphological properties of the gel matrix were comprehensively investigated. The results showed that the novel ChWs/PVA hydrogels were facilely constructed from sequential chemical cross-linking and physical cross-linking with GA. The hydrogel with the ChWs to PVA weight ratios of 40% achieved the highest equilibrium swelling ratio, and could release more than 80% of the BSA from its gel matrix within 75 h.


Asunto(s)
Quitina/química , Portadores de Fármacos/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Hidrogeles/química , Nanopartículas/química , Alcohol Polivinílico/química , Materiales Biocompatibles/química , Liberación de Fármacos , Ensayo de Materiales , Nanopartículas/ultraestructura , Análisis Espectral
18.
Onco Targets Ther ; 11: 5075-5082, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30174445

RESUMEN

BACKGROUND/PURPOSE: Given the emerging role of microRNA (miRNA) in cancer progression, we investigated the role and mechanism of miRNA-543 (miR-543) in gastric cancer (GC). MATERIALS AND METHODS: Real-time quantitative polymerase chain reaction was conducted to quantify the expression of miR-543. Luciferase reporter assay was used to confirm the association between speckle-type POZ protein (SPOP) and 3'-UTR. Moreover, the role of miR-543 and SPOP in GC was detected using transwell assays. In addition, we investigated the function of miR-543 in the epithelial-mesenchymal transition (EMT) progression. RESULTS: miR-543 was upregulated in GC. We identified SPOP as a direct target of miR-543, revealing its expression to be inversely correlated with miR-543 expression in GC tissues. Moreover, restoration of SPOP could inhibit miR-543-induced GC cell migration and invasion, whereas downregulation of miR-543 inhibited cell migration and invasion, which was partly abrogated by SPOP knockdown. Furthermore, our data also showed that miR-543 induced EMT of GC cells. CONCLUSION: Our results demonstrated that miR-543 functions as a crucial oncogenic miRNA in GC. It exerts strong tumor-promoting effects through targeting SPOP in GC cell migration and invasion.

19.
Mol Med Rep ; 17(1): 783-788, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29115525

RESUMEN

Given the emerging role of microRNAs (miRs) in cancer progression, the present study investigated the role and underlying mechanism of miR­103 in colorectal cancer (CRC). Reverse transcription­quantitative polymerase chain reaction was conducted to quantify the expression levels of miR­103 in clinical specimens and cell lines. The role of miR­103 in CRC was examined using MTT, colony formation and transwell assays. In addition, a luciferase reporter assay was used to confirm an associated between the 3' untranslated region of zonula occuldens­1 (ZO­1) and miR­103. The results demonstrated that miR­103 was upregulated in CRC. Overexpression of miR­103 promoted CRC cell proliferation and migration in vitro, whereas downregulation of miR­103 inhibited cell proliferation and migration. ZO­1 was identified as a direct target of miR­103, revealing its expression to be inversely correlated with miR­103 expression in CRC samples. In conclusion, the present study revealed that miR­103 has strong tumor­promoting effects via of targeting ZO­1 in CRC and has potential development of miRNA­based targeted approaches for the treatment of CRC.


Asunto(s)
Transformación Celular Neoplásica/genética , Neoplasias Colorrectales/genética , MicroARNs/genética , Interferencia de ARN , Proteína de la Zonula Occludens-1/genética , Regiones no Traducidas 3' , Movimiento Celular/genética , Proliferación Celular/genética , Supervivencia Celular/genética , Transformación Celular Neoplásica/metabolismo , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Biología Computacional/métodos , Regulación Neoplásica de la Expresión Génica , Genes Reporteros , Humanos , Proteína de la Zonula Occludens-1/metabolismo
20.
J Agric Food Chem ; 66(4): 935-942, 2018 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-29283261

RESUMEN

Natural hydrogels have attracted extensive research interest and shown great potential for many biomedical applications. In this study, a series of biocompatible hydrogels was reported based on the self-assembly of positively charged partially deacetylated α-chitin nanofibers (α-DECHN) and negatively charged 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose nanofibers (TOCNF) for anticancer drug delivery. The formation mechanisms of the α-DECHN/TOCNF hydrogels with different mixing proportions were studied, and their morphological, mechanical, and swelling properties were comprehensively investigated. Additionally, the drug delivery performance of the hydrogels was compared via sustained release test of an anticancer drug (5-fluorouracil). The results showed that the hydrogel with higher physical cross-linking degree exhibited a higher drug loading efficiency and drug release percentage.


Asunto(s)
Antineoplásicos/administración & dosificación , Materiales Biocompatibles , Quitina/química , Óxidos N-Cíclicos/química , Sistemas de Liberación de Medicamentos , Nanofibras/química , Celulosa/química , Reactivos de Enlaces Cruzados , Preparaciones de Acción Retardada , Fluorouracilo/administración & dosificación , Hidrogeles
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