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1.
Small ; 18(9): e2106225, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34910853

RESUMO

High-voltage lithium metal batteries (LMBs) are a promising high-energy-density energy storage system. However, their practical implementations are impeded by short lifespan due to uncontrolled lithium dendrite growth, narrow electrochemical stability window, and safety concerns of liquid electrolytes. Here, a porous composite aerogel is reported as the gel electrolyte (GE) matrix, made of metal-organic framework (MOF)@bacterial cellulose (BC), to enable long-life LMBs under high voltage. The effectiveness of suppressing dendrite growth is achieved by regulating ion deposition and facilitating ion conduction. Specifically, two hierarchical mesoporous Zr-based MOFs with different organic linkers, that is, UiO-66 and NH2 -UiO-66, are embedded into BC aerogel skeletons. The results indicate that NH2 -UiO-66 with anionphilic linkers is more effective in increasing the Li+ transference number; the intermolecular interactions between BC and NH2 -UiO-66 markedly increase the electrochemical stability. The resulting GE shows high ionic conductivity (≈1 mS cm-1 ), high Li+ transference number (0.82), wide electrochemical stability window (4.9 V), and excellent thermal stability. Incorporating this GE in a symmetrical Li cell successfully prolongs the cycle life to 1200 h. Paired with the Ni-rich LiNiCoAlO2 (Ni: Co: Al = 8.15:1.5:0.35, NCA) cathode, the NH2 -UiO-66@BC GE significantly improves the capacity, rate performance, and cycle stability, manifesting its feasibility to operate under high voltage.


Assuntos
Lítio , Estruturas Metalorgânicas , Fontes de Energia Elétrica , Eletrólitos , Ácidos Ftálicos
2.
Chemistry ; 27(38): 9876-9884, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-33878217

RESUMO

The shuttling of polysulfides is the most detrimental contribution to degrading the capacity and cycle stability of lithium-sulfur (Li-S) batteries. Adding a carbon interlayer to prevent the polysulfides from migrating is feasible, and a rational design of the structures and surface properties of the carbon layer is essential to increasing its effectiveness. Herein, we report a hierarchical porous carbon (HPC) created by carbonization of bis(phenoxy)phosphazene and in-situ doping of triple heteroatoms into the carbon lattice to fabricate an effective polysulfide-trapping interlayer. The generated carbon integrates the advantages of a hierarchical porous structure, a high specific area and rich dopants (N, O and P), to yield chemisorption and physical confinement for polysulfides and fast ion-transport synergistically. The HPC interlayer significantly improves the electrochemical performance of Li-S batteries, including an exceptional discharge capacity of 1509 mA h/g at 0.06 C and a high capacity retention of 83.7 % after 250 cycles at 0.3 C. This work thus proposes a facile in-situ synthesis of heteroatom-doped carbon with rational porous structures for suppressing the shuttle effect.

3.
Small ; 16(11): e1906883, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32080974

RESUMO

Developing supermechanically resilient hard carbon materials that can quickly accommodate sodium ions is highly demanded in fabricating durable anodes for wearable sodium-ion batteries. Here, an interconnected spiral nanofibrous hard carbon fabric with both remarkable resiliency (e.g., recovery rate as high as 1200 mm s-1 ) and high Young's modulus is reported. The hard carbon nanofabrics are prepared by spinning and then carbonizing the reaction product of polyacrylonitrile and polar molecules (melamine). The resulting unique hard carbon possesses a highly disordered carbonaceous structure with enlarged interlayer spacing contributed from the strong electrostatic repulsion of dense pyrrolic nitrogen atoms. Its excellent resiliency remains after intercalation/deintercalation of sodium ions. The outstanding sodium-storage performance of the derived anode includes excellent gravimetric capacity, high-power capability, and long-term cyclic stability. More significantly, with a high loading mass, the hard carbon anode displays a high-power capacity (1.05 mAh cm-2 at 2 A g-1 ) and excellent cyclic stability. This study provides a unique strategy for the design and fabrication of new hard carbon materials for advanced wearable energy storage systems.

4.
Environ Sci Technol ; 54(19): 12042-12050, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32936622

RESUMO

Design and fabrication of bimodal structures are essential for successful development of advanced air filters with ultralow airflow resistance. To realize this goal, simplified processing procedures are necessary for meeting the practical needs. Here, a bimodal protein fabric with high-performance air filtration, and effectively lowered airflow resistance is reported. The various functional groups of proteins provide versatile interactions with pollutants. By utilizing a novel and cost-effective "cross-axial" configuration with an optimized condition (75° of contacting angle between solution nozzle and cospinning solvent nozzle), the diffusion in Taylor cone is in situ controlled, which results in the successful production of bimodal protein fabric. The bimodal protein fabric (16.7 g/m2 areal density) is demonstrated to show excellent filtration performance for removing particulate matter (PM) pollutants and only causes 17.1 Pa air pressure drop. The study of multilayered protein fabric air filters shows a further improvement in filtration performance of removing 97% of PM0.3 and 99% of PM2.5 with a low airflow resistance (34.9 Pa). More importantly, the four-layered bimodal protein fabric shows an exceptional long-term performance and maintains a high removal efficiency in the humid environment. This study presents an effective and viable strategy for fabricating bimodal fibrous materials for advanced air filtration.


Assuntos
Filtros de Ar , Difusão , Filtração , Material Particulado
5.
Small ; 14(49): e1803564, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30369068

RESUMO

Incorporating nanofillers is one of the promising approaches for simultaneously boosting the ionic conductivity and mechanical properties of solid polymer electrolytes (SPEs). However, effectively creating faster ion-conduction pathways via nanofillers still remains a big challenge. Herein, core-shell protein-ceramic nanowires for more efficiently building fast ion-conduction networks in SPEs are reported. The core-shell protein-ceramic nanowires are fabricated via in situ growth of protein coating on the electrospun TiO2 nanowires in a subtly controlled protein-denaturation process. It is demonstrated that the core-shell protein@TiO2 nanowires effectively facilitate ion-conduction. As a result, the ionic conductivity, mechanical properties, electrochemical stability, and even Li+ transference number of the SPEs with core-shell protein@TiO2 nanowires are significantly enhanced. The contributions from the 1D morphology of the protein@TiO2 nanowires, and more importantly, the favorable protein structure for further promoting ion-conduction at the polymer-filler interfaces are analyzed. It is believed that the protein plays a pivotal role in dissociating lithium salts, which benefits from the strong interactions between protein and ions, making the protein serve as a unique "natural channel" for rapidly conducting Li+ . This study initiates an effective method of promoting ionic conductivity and constructing faster ion-conduction networks in SPEs via combining bio- and nanotechnology.

6.
Nano Lett ; 14(6): 3474-80, 2014 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-24813371

RESUMO

Nanofabrication has been critical in all kinds of nanotechnology, not only for achieving various nanostructures or nanosystems but also for the application of the nanotechnology. To achieve controllable but simple nanofabrication is one of the central aspirations for many research communities; here, for the first time, we report the growth of nanosheet structures simply by introducing internal disturbances (adding nanoparticles and surface tension) or external disturbances (deformations) to the self-assembly of copolymers induced by evaporation. Nanoparticles, curved surface, and deformations by such as writing or extension have been employed to demonstrate the sensitivity of the nanosheet structures to various disturbances. Finally, a physical model has been proposed to explain how the disturbances contribute to the formation of the nanosheet structures. These significant results indicate a scalable, writable, cost-effective and environmentally friendly nanotechnology that will stimulate new nanofabrication research.

7.
Zhongguo Zhong Yao Za Zhi ; 40(7): 1419-24, 2015 Apr.
Artigo em Zh | MEDLINE | ID: mdl-26281573

RESUMO

In this paper, an analysis was made on the varieties and standards of labiatae medicinal plants used in Tibetan medicine. The results showed 71 species of labiatae plants in 21 genera (including varieties) recorded in relevant literatures, involving 44 varieties of medicinal materials. Specifically, seven species (9.9%) were intersected with traditional Chinese medicines (TCM), 19 varieties (43%) were recorded in Chinese medicinal material standards at all levels, and 27 species (38%) were source plants. In Tibetan medicine standards and literatures, there are great differences between Tibetan names and translated Chinese names and among varieties of source plants. Apart from a few of varieties intersected with traditional Chinese medicines had complete standards and regulations in Chinese Pharmacopoeia, most of species only had characters, microscopic, physical and chemical identifications in Standards Issued by Ministry of Health-Tibetan Medicine, Tibetan Medicine Standard and local standards. Therefore, the Tibetan medicinal material variety-source specification and quality standard system shall be promoted on the basis of literatures research, investigations for resources and current applications and modern pharmaceutical studies.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Lamiaceae/química , Medicina Tradicional Tibetana/normas , Fitoterapia/normas , Plantas Medicinais/química , Medicamentos de Ervas Chinesas/química , Humanos , Lamiaceae/classificação , Plantas Medicinais/classificação
8.
Zhongguo Zhong Yao Za Zhi ; 40(23): 4686-92, 2015 Dec.
Artigo em Zh | MEDLINE | ID: mdl-27141684

RESUMO

In this paper, the popular domestic varieties and quality standard of Scrophulariaceae plants used in Tibetan medicine were analyzed. The results showed that there were 11 genera and 99 species (including varieties), as well as 28 medicinal materials varieties of Scrophulariaceae plants were recorded in the relevant literatures. In relevant Tibetan standards arid literatures, there are great differences in varieties, sources, parts, and efficacies of medicinal plant. Among them, about 41.4% (including 41 species) of endemic plants, about 15.2% (including 15 species) of the original plants have medicinal standard legal records, except the medicinal materials of Scrophalaria ningpoensis, Lagotis brevituba, Picrorhiza scrophulariiflora, Veronica eriogyne general, most varieties have not completed quality standard. Consequently it is necessary to reinforce the herbal textual, resources and the use present situation investigation, the effects of the species resources material foundation and biological activity, quality standard, specification the medical terms of the plants, and promote Tibetan medicinal vareties-terminologies-sources such as the criterion and quality standard system for enriching the varieties of Tibetan medicinal materials and Chinese medicinal resources.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Medicina Tradicional Tibetana/normas , Plantas Medicinais/classificação , Scrophulariaceae/classificação , Medicamentos de Ervas Chinesas/química , Humanos , Plantas Medicinais/química , Scrophulariaceae/química
9.
Zhongguo Zhong Yao Za Zhi ; 40(24): 4914-22, 2015 Dec.
Artigo em Zh | MEDLINE | ID: mdl-27245043

RESUMO

In this paper, the domestic varieties and quality standard of Leguminosae medicinal plants used in Tibetan medicine were analyzed. The results showed that there were 36 genera and 142 species (including varieties), as well as 64 medicinal materials varieties of Leguminosae plants were recorded in relevant literatures. In relevant Tibetan standards and literatures, there are great differences in varieties, sources, used parts, and efficacy of medicinal plants. Among them, about 38.0% (including 54 species) of the endemic plants, about 25.4% (including 36 species) of the original plants have medicinal standard legal records, except 9 kinds of traditional Chinese medicine general quality standard more fairly completed, the most varieties have only description about characters, identification, etc. Therefore it is necessary to reinforce study for the herbal textual, resources and the use present situation, chemical components and biological activity, quality standard, medicinal terms specification, to promote establishment of quality standard system for variety-terminologies-sources of Tibetan medicinal plants.


Assuntos
Fabaceae , Medicina Tradicional Tibetana , Medicina Tradicional Tibetana/normas
10.
ACS Appl Mater Interfaces ; 16(12): 15632-15639, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38489749

RESUMO

Fundamentally suppressing Li dendrite growth is known to be critical for realizing the potential high energy density for Li-metal batteries (LMBs). Inspired by the ionic transport function of proteins, we previously discovered that utilizing natural proteins was able to stabilize the Li anode but have not demonstrated how a specific amino acid of the protein enabled the function. In this study, we decorate the separator with Leucine (Leu) amino acid assisted by poly(acrylic acid) (PAA) for effectively stabilizing the Li-metal anode, so as to dramatically improve the cycling performance of LMBs. The decorated separator improves electrolyte wettability and effectively suppresses Li dendrite growth. As a result, the amino acid-enabled separator prolongs the cycle life of the symmetrical Li|Li cells, exhibits higher Coulombic efficiency in the Li|Cu cells, and improves the cycling performance in LMBs with the LiFePO4 cathode. This work is an initial study on applying a specific amino acid of proteins to enhance the performance of batteries, providing a new strategy on guiding Li+ deposition, and laying an important foundation for functional separator design of high-energy-density batteries.

11.
Carbohydr Polym ; 321: 121308, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37739538

RESUMO

Cellulose-based conductive composite fibers hold great promise in smart wearable applications, given cellulose's desirable properties for textiles. Blending conductive fillers with cellulose is the most common means of fiber production. Incorporating a high content of conductive fillers is demanded to achieve desirable conductivity. However, a high filler load deteriorates the processability and mechanical properties of the fibers. Here, developing wet-spun cellulose-based fibers with a unique side-by-side (SBS) structure via sustainable processing is reported. Sustainable sources (cotton linter and post-consumer cotton waste) and a biocompatible intrinsically conductive polymer (i.e., polyaniline, PANI) were engineered into fibers containing two co-continuous phases arranged side-by-side. One phase was neat cellulose serving as the substrate and providing good mechanical properties; another phase was a PANI-rich cellulose blend (50 wt%) affording electrical conductivity. Additionally, an eco-friendly LiOH/urea solvent system was adopted for the fiber spinning process. With the proper control of processing parameters, the SBS fibers demonstrated high conductivity and improved mechanical properties compared to single-phase cellulose and PANI blended fibers. The SBS fibers demonstrated great potential for wearable e-textile applications.

12.
ACS Appl Mater Interfaces ; 14(38): 43886-43896, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36099531

RESUMO

With plenty of charges and rich functional groups, bovine serum albumin (BSA) protein provides effective transport for multiple metallic ions inside blood vessels. Inspired by the unique ionic transport function, we develop a BSA protein coating to stabilize Li anode, regulate Li+ transport, and resolve the Li dendrite growth for Li metal batteries (LMBs). The experimental and simulation studies demonstrate that the coating has strong interactions with Li metal, increases the wetting with electrolyte, reduces the electrolyte/Li side reactions, and significantly suppresses the Li dendrite formation. As a result, the BSA coating exhibits excellent stability in the electrolyte and improves the performance of Li|Cu and Li|Li cells as well as the LiFePO4|Li batteries. This work reveals that LMBs can benefit from the biological function of BSA, i.e., special transport capability of metallic ions, and lays an important foundation in design of protein-based materials for effectively enhancing the electrochemical performance of energy storage systems.


Assuntos
Lítio , Soroalbumina Bovina , Fontes de Energia Elétrica , Eletrodos , Íons
13.
J Ethnopharmacol ; 286: 114922, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-34923087

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Hepatocyte lipid accumulation is the main feature in the early stage of nonalcoholic fatty liver disease (NAFLD). Highland barley Monascus purpureus Went (HBMPW), a fermentation product of Hordeum vulgare Linn. var. nudum Hook. f. has traditionally been used as fermented foods in Tibet with the effect of reducing blood lipid in folk medicine. AIM OF THE STUDY: This study investigated the protective effects and molecular mechanism of highland barley Monascus purpureus Went extract (HBMPWE) on NAFLD in syrian golden hamster fed with high-fat, high-fructose, high-cholesterol diet (HFFCD). MATERIALS AND METHODS: HFFCD-induced NAFLD golden hamster model was established and treated with HBMPWE. Liver index, biochemical index, and hematoxylin and eosin (HE) staining were observed. Liver metabolomics and western blot analysis were employed. RESULTS: Our study found that HBMPWE ameliorated HFFCD induced dyslipidemia, weight gain and elevated the liver index. In addition, HBMPWE treatment significantly attenuated lipid accumulation in the liver and modulated lipid metabolism (sphingolipid, glycerophospholipid). Our data demonstrated that HBMPWE not only regulated the expression of proteins related to fatty acid synthesis and decomposition (SREBP-1/ACC/FAS/AceS1, PPARα/ACSL/CPT1/ACOX1), but also regulated the expression of proteins related to cholesterol synthesis and clearance (HMGCR, LDLR, CYP7A1). CONCLUSIONS: HBMPWE improved NAFLD through multiple pathways and multiple targets in body metabolism and could be used as a functional food to treat NAFLD and other lipid metabolic disorders.


Assuntos
Alimentos Fermentados , Metabolismo dos Lipídeos/efeitos dos fármacos , Monascus/metabolismo , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Animais , Dieta Hiperlipídica , Modelos Animais de Doenças , Ácidos Graxos/biossíntese , Frutose , Hordeum/metabolismo , Masculino , Medicina Tradicional Tibetana , Mesocricetus , Tibet
14.
J Nanosci Nanotechnol ; 11(5): 3929-37, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21780388

RESUMO

In this study we report the advantages of a 2-step method that incorporates an additional process pre-conditioning step for rapid and precise blending of the constituents prior to the commonly used melt compounding method for preparing polycarbonate/oxidized carbon nanofiber composites. This additional step (equivalent to a manufacturing cell) involves the formation of a highly concentrated solid nano-nectar of polycarbonate/carbon nanofiber composite using a solution mixing process followed by melt mixing with pure polycarbonate. This combined method yields excellent dispersion and improved mechanical and thermal properties as compared to the 1-step melt mixing method. The test results indicated that inclusion of carbon nanofibers into composites via the 2-step method resulted in dramatically reduced ( 48% lower) coefficient of thermal expansion compared to that of pure polycarbonate and 30% lower than that from the 1-step processing, at the same loading of 1.0 wt%. Improvements were also found in dynamic mechanical analysis and flexural mechanical properties. The 2-step approach is more precise and leads to better dispersion, higher quality, consistency, and improved performance in critical application areas. It is also consistent with Lean Manufacturing principles in which manufacturing cells are linked together using less of the key resources and creates a smoother production flow. Therefore, this 2-step process can be more attractive for industry.

15.
ChemSusChem ; 14(10): 2226-2236, 2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-33754482

RESUMO

Lithium-sulfur (Li-S) batteries are a promising candidate for the next-generation energy storage system, yet their commercialization is primarily hindered by polysulfide shuttling and uncontrollable Li dendrite growth. Here, a protein-based Janus separator was designed and fabricated for suppressing both the shuttle effect and dendrite growth, while facilitating the Li+ transport. The Li metal-protecting layer was a protein/MoS2 nanofabric with high ionic conductivity and good Li+ affinity, thus capable of homogenizing the Li+ flux and facilitating the Li+ transport. The polysulfide-trapping layer was a conductive protein nanofabric enabling strong chemical/electrostatic interactions with polysulfides. Combination of the two layers was achieved by an integrated electrospinning method, yielding a robust and integral Janus separator. As a result, a long-lived symmetric Li|Li cell (>700 h) with stable cycling performance was demonstrated. More significantly, the resulting Li-S battery delivered greatly improved electrochemical performance, including excellent rate capacity and remarkable cycle stability (with a low decay rate of 0.063 % per cycle at 0.5 A g-1 over 500 cycles). This study demonstrates the effectiveness of the Janus separator configurations for simultaneously addressing the shuttle effect and dendrite growth issues of Li-S batteries and broadens the applications of electrospinning in electrochemistry community.

16.
J Hazard Mater ; 415: 125742, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34088201

RESUMO

Building bimodal structures for air-filters is promising to reduce the airflow resistance without sacrificing the filtration efficiency. To do so, multi-jet electrospinning is among the most broadly used methods, yet the interplay between single fibers in electrospinning, which is significant to their morphologies, is overlooked. In this study, we report a wettability difference-driven strategy to fabricate a bimodal protein fabric with superior filtration performance. We surprisingly find that only by co-spinning of two proteins, zein and gelatin, with different wettability between them, a drastic change of fiber diameters is spontaneously achieved. The generated protein-blend fabric possesses bimodally distributed diameters of 270 nm for gelatin fibers and of 1.12 µm for zein fibers; both pure protein fabrics via single-jet electrospinning have diameters unimodally distributed in the range of 500-700 nm. The bimodal protein-blend fabric delivers exceptional removal efficiencies of 99.67% for PM2.5 and 98.80% for PM0.3, yielding an ultra-low airflow resistance of 38 Pa. The PM2.5 removal efficiency retains to be 96.04% after filtering 1000 L polluted air, indicating a good long-term performance. This study brings about a new insight into fabrication of bimodal structures using multi-jet electrospinning method and promotes the development of natural products for broad applications.

17.
J Phys Chem Lett ; 12(39): 9429-9435, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34554749

RESUMO

Decoupling the ion motion and segmental relaxation is significant for developing advanced solid polymer electrolytes with high ionic conductivity and high mechanical properties. Our previous work proposed a decoupled ion transport in a novel protein-based solid electrolyte. Herein, we investigate the detailed ion interaction/transport mechanisms through first-principles density functional theory (DFT) calculations in a vacuum space. Specifically, we study the important roles of charged amino acids from proteins. Our results show that the charged amino acids (i.e., Arg and Lys) can strongly lock anions (ClO4-). When locked at a proper position (determined from the molecular structure of amino acids), the anions can provide additional hopping sites and facilitate Li+ transport. The findings are supported from our experiments of two protein solid electrolytes, in which the soy protein (with plenty of charged amino acids) electrolyte shows much higher ionic conductivity and lower activation energy in comparison to the zein (lack of charged amino acids) electrolyte.


Assuntos
Teoria da Densidade Funcional , Eletrólitos/química , Proteínas de Soja/química , Aminoácidos/metabolismo , Ânions/química , Condutividade Elétrica , Eletrólitos/metabolismo , Transporte de Íons , Lítio/química , Lítio/metabolismo , Proteínas de Soja/metabolismo
18.
ACS Appl Mater Interfaces ; 13(7): 8736-8744, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33565848

RESUMO

Integrating nanostructured active materials, antimicrobial components, and rational porous structures is one of the promising approaches for simultaneously boosting removal efficiency, antimicrobial capacity, mechanical property, hydrophobic performance, and air permeability of air filters. However, realizing these performances of an air filter still remains a big challenge. Herein, a multifunctional air filter zNFs-Ag@PT, which is composed of a unique substrate prepared from Ag nanoparticles (AgNPs)-paper towel (PT) microfibers and an upper layer formed from aligned zein nanofibers (zNFs) inspired by a "tug-of-war" repulsion force, is reported. The Ag@PT substrate is fabricated via in situ reduction; and zNFs are prepared by electrospinning a well-prepared zein Pickering emulsion onto a specially designed collector. The innovative collector is a partially conductive design composed of an insulative middle section and two conductive ends. It is demonstrated that the introduction of AgNPs not only endows the zNFs-Ag@PT filter with an effective antimicrobial activity but also provides the substrate with an anisotropic electric field to achieve stretched and aligned zein fibers forming thinner nanofibers than that without AgNPs. As a result, the filtration performances of a zNFs-Ag@PT filter are enhanced. This study initiates an effective way to fabricate bio-based multifunctional air filters with antimicrobial and filtration performances via combining nano- and biotechnology.

19.
Undersea Hyperb Med ; 37(3): 141-50, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20568543

RESUMO

OBJECTIVE: We investigated the effects of hyperbaric oxygen (HBO2) and/or 5-fluorouracil (5-FU) on the proliferation and metastasis of human nasopharyngeal carcinoma (NPC) cell line CNE2Z and the underlying mechanisms involved. METHODS: Nasopharyngeal carcinoma (NPC) CNE2Z cells were randomly divided into four groups: Group A: control group; Group B: 5-FU group; Group C: HBO2 group; Group D: 5-FU plus HBO2 group. The inhibitory effects on CNE2Z cells proliferation in the four groups after 24, 48 and 72 hours of treatment were measured by MTT-colorimetric method. Transwell chamber assay was performed to determine the effects of HBO2 and/or 5-FU on the metastasis of CNE2Z cells; Expressions of MMP-9 and VEGF in CNE2Z cells were detected by immunocytochemical staining. RESULT: A significant difference was observed in the inhibitory effects on CNE2Z cell proliferation (OD values) between the 5-FU group (Group B) and the control group (Group A) after 24, 48, and 72 hours of treatment (p<0.01); between the HBO2 group (group C) and the control group (Group A) after 48 and 72 hours of treatment (p<0.01); and between the HBO2 plus 5-FU group (Group D) and the control group (Group A) as well as the HBO2 plus 5-FU group (Group D) and the HBO2 group (Group C) after 24, 48, and 72 hours of treatment (p<0.01). But a significant difference between the HBO2 plus 5-FU group (Group D) and the 5-FU group (Group B) was observed only after 48 hours of treatment (p=0.030). As for metastasis, as well as MMP-9 and VEGF expression OD values, significant difference was observed between the 5-FU group (Group B) and the control group (Group A) with p<0.05, but not between the HBO2 group (Group C) and the control group (Group A). Although effects on metastasis as well as MMP-9 and VEGF expression OD values were significantly different between the 5-FU plus HBO group (group D) and group A (p<0.01), no difference was observed between Group D and Group B as well as Group D and Group C. CONCLUSIONS: Simple HBO2 treatment after 48 and 72 hours could inhibit the proliferation of nasopharyngeal carcinoma CNE2Z cells. The combination of HBO2 with 5-FU exhibited significant synergism in the suppression of NE2Z cell proliferation only after 48 hours of treatment compared to 5-FU. Simple HBO2 treatment could not reduce the high expressions of MMP-9 and VEGF and inhibit the metastasis of human NPC CNE2Z cells, and no synergistic effect was observed for the combination of HBO2 with 5-FU compared to 5-FU alone.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Fluoruracila/uso terapêutico , Oxigenoterapia Hiperbárica , Neoplasias Nasofaríngeas/terapia , Antimetabólitos Antineoplásicos/administração & dosagem , Linhagem Celular Tumoral , Ensaios de Migração Celular/métodos , Terapia Combinada/métodos , Fluoruracila/administração & dosagem , Humanos , Concentração Inibidora 50 , Metaloproteinase 9 da Matriz/metabolismo , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia , Invasividade Neoplásica , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular/metabolismo
20.
Nanoscale ; 12(9): 5483-5493, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32083635

RESUMO

Developing flexible, robust and lightweight sulfur cathodes by rationally designing their structures and configurations through a viable and scalable strategy is a critical enabler for fulfilling flexible lithium-sulfur (Li-S) batteries. However, besides the requirements for cathode flexibility, intrinsic limitations from the shuttling of lithium polysulfides and the growth of Li dendrites have restricted the widespread implementations of Li-S batteries. Here, we report a wet-processed strategy by dissolving and recrystallizing S in a suitable solvent to fabricate a flexible, binder-free S cathode. Integrating the resulting S cathode with a dual-functional separator has demonstrated to be able to suppress both the shuttle effect and growth of dendritic Li. The wet-processed strategy not only enables the fabrication of flexible and binder-free S-nanomat cathodes, but also facilitates the deposition of the cathodes on the separators. Meanwhile, a dual-functional separator is fabricated by vapor-phase polymerization of polypyrrole (PPy) coating on both surfaces of the commercial separator, which leads to the reduction of the shuttle effect and the suppression of the growth of dendritic Li simultaneously. As a result, by integrating the S-nanomat and the dual-functional separator, the cathode exhibits exceptional mechanical properties and electrochemical performance. Li-S pouch cells are further demonstrated to show stable cycling performance in the bending state, indicating the feasibility of the integrated S cathode for flexible Li-S batteries.

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