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1.
ACS Appl Mater Interfaces ; 16(3): 3888-3900, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38196337

RESUMEN

The severe shuttle effect and the depletion of active sulfur result in performance deterioration, presenting two formidable issues that must be overcome to achieve high-mass-loading lithium-sulfur batteries. Herein, we reported a composite separator by introducing carbon photonic crystals with a hierarchically ordered porous structure on a commercial separator. The ordered structure and interconnected hierarchical macro-meso-micropore network of the composite separator facilitate efficient trapping of polysulfides and rapid transport of lithium ions. The high ion diffusivity promotes the conversion of polysulfides enhancing sulfur utilization and mitigating the occurrence of "dead sulfur" on the surface of the separator. Impressively, under a high sulfur loading of 3 mg cm-2, the lithium-sulfur battery with the composite separator displayed a high reversible capacity of 1582 mA h g-1 at 0.1 C and an excellent long-term cycling performance with a decay rate of as low as 0.033% per cycle over 1500 cycles at 1 C. Surprisingly, the battery represented a high reversible capacity of 935 mA h g-1 at 0.2 C even at a sulfur loading of 6.71 mg cm-2. The design of the composite separator underscores the pivotal role of carbon architecture in improving battery performance and brings a bright prospect to enable the commercialization of high-mass-loading lithium-sulfur batteries.

2.
Small ; : e2309702, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38087966

RESUMEN

MXene nanosheets and ordered porous carbons both have their own advantages and disadvantages. Assembling and combining the advantages of the two will be a good choice for battery electrode hosts of active materials. In this work, an electrostatic separation-adsorption strategy is proposed to realize the ordered alternating self-assembly of MXene nanosheets and ordered porous carbon (MPOC), obtaining a unique wall-like porous material with a high conductivity and interconnected porous nanostructure, which strengthens the transfer rate of electrons and ions simultaneously. Meanwhile, the introduction of N-doping from porous carbon into MPOC prolongs the cycle life. When use red phosphorus (RP) as active materials, the MPOC@RP anode exhibited high-capacity output (2454.3 and 2408.1 mAh g-1 in lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) at 0.1 C) and long cycle life (the decay rates per cycle of 0.028% and 0.036% after 1500 and 1200 cycles at 2 C in LIBs and SIBs respectively). The successful application in RP anodes displays great potential in other electrode materials such as silicon, sulfur, selenium, and so on. Meanwhile, this strategy is also effective to design other composites materials like MXene and carbon nanotubes, MXene and Graphene, and so on.

3.
Environ Sci Technol ; 57(21): 8002-8014, 2023 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-37204768

RESUMEN

Eutrophication and exotic species invasion are key drivers of the global loss of biodiversity and ecosystem functions in lakes. We selected two exotic plants (Alternanthera philoxeroides and Myriophyllum aquaticum) and two native plants (Myriophyllum spicatum and Vallisneria spinulosa) to elucidate the effect of eutrophication on exotic plant invasiveness. We found that (1) elevated nutrient favored invasion of exotic species and inhibited growth of native plants. Species combinations and plant densities of native plants had limited effects on the resistance to invasion of the exotics. (2) A. philoxeroides featured the tightest connectivity among traits, which is consistent with its high competitive ability. Although eutrophication caused physiological stress to A. philoxeroides, it could effectively regulate enzyme activity and alleviate the stress. (3) M. aquaticum possessed strong tolerance to habitat disturbance and was highly disruptive to the surrounding plants. Eutrophication will exacerbate the adverse effects of M. aquaticum on the littoral ecosystem. (4) Nutrient enrichment reduced the biomass and relative growth rates of V. spinulosa and lowered phenolics and starch contents of M. spicatum, thereby making them more susceptible to habitat fluctuations. Overall, our study highlights how eutrophication alters the invasiveness of exotic plants and the resistance of native plants in the littoral zone, which is of relevance in a world with intensified human activities.


Asunto(s)
Ecosistema , Lagos , Humanos , Especies Introducidas , Plantas , Eutrofización
5.
ACS Nano ; 2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36594423

RESUMEN

Designing nanostructured hosts with the merits of high conductivity, strong trapping ability, and long-term durability to improve the insulating nature and extreme volume change of red phosphorus (RP) is a promising option for the development of high-performance lithium/sodium-ion batteries (LIBs/SIBs). Here, a multifunctional RP immobilizer is proposed and fabricated, which comprises a nitrogen-doped hollow MXene sphere (NM) planted with the dual-sided porous carbon network (DCNM). In such a configuration, the highly conductive macroporous NM not only facilitates fast electron transport but also acts as the capturing center to entrap polyphosphide through strong chemical adsorption, while the uniformly distributed micromesoporous carbon network in or out of the sphere provides reliable RP accommodation and alleviates the volume expansion, as well as creates interpenetrating ion diffusion and electron transport channels. Benefiting from the synergistic effect of the triple-shelled architecture and the exclusive restraint, the Hoya-like DCNM@RP anode exhibits significantly enhanced electrochemical performances for LIBs and SIBs, delivering a combination of high reversible capacity, splendid rate properties, and extended cycling performance: up to 1800 cycles with 0.01% per cycle capacity decay for LIBs and 0.024% per cycle over 1000 cycles for SIBs at 2 C.

6.
J Colloid Interface Sci ; 623: 318-326, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35594590

RESUMEN

Since of their adjustable pore structure and variety of metal sites, MOFs materials have infinite possibilities, but their low intrinsic activity hinders them from being employed in electrolytic water. The sulfurization and oxidation of MOFs has proven to be a feasible technique for producing highly active catalytic materials. Here, the MOFs are completely converted to hydroxide by treatment with alkaline solutions only. Electron microscopy demonstrates that hydroxides generated from various MOFs retain the complete profile of the precursor and contain a two-dimensional lamellar or mesoporous structure. Fe-MIL-88(A)-OH, a two-dimensional structural transformation product generated from Fe-MIL-88(A), demonstrates significant OER performance increase. At the same 300 mV overpotential, Fe-MIL-88(A)-OH delivers 83 times the current density of Fe-MIL-88(A) and 16 times that of commercial IrO2 (22.56 mA cm-2 vs. 0.27 mA cm-2 vs. 1.37 mA cm-2). The alkali treatment strategy proved to be a generally applicable treatment for MOFs, allowing the conversion of nickel- and cobalt-based MOFs to hydroxide with a significant boost in OER performance.

7.
Small ; 18(11): e2106930, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35023633

RESUMEN

The natural insulating property and notorious pulverization of volume variation-induced materials during cycling pares the electrochemical activity of red phosphorous (RP) for lithium/sodium-ion batteries (LIBs/SIBs). To work out these issues, a tailored trimodal porous carbon support comprising highly ordered macropores and micro-mesoporous walls embedded with copper (Cu) nanoclusters (Cu-OMC) is proposed to confine RP. The construction of highly conductive copper-carbon wall facilitates fast electrons and ions transportation, while the interconnected and ordered porous structure not only creates enough space to resist the expansion effect of RP but also minimizes the ion diffusion length and enhances ion accessibility (the ion migration coefficient is ten times that of disordered porous carbon). Consequently, the resulting Cu-OMC@RP anode delivers a high reversible capacity (2498.7 mAh g-1 at 0.3 C for LIBs; 2454.2 mAh g-1 at 0.1 C for SIBs), superb rate properties (824.7 mAh g-1 at 10 C for LIBs; 774.2 mAh g-1 at 5 C for SIBs), and outstanding cycling stability (an ultralow decay rate of 0.057% per cycle after 1000 cycles at 10 C for LIBs and 0.048% per cycle at 5 C over 500 cycles for SIBs).

8.
Small ; 18(7): e2104224, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34866332

RESUMEN

Lithium batteries with high electrode thickness always possess a poor battery property due to electrode polarization along the thickness direction. Herein, a concept that the electrode polarization can be reduced through the fabrication of 3D ordered interconnected nanostructure in the electrode is put forward. A nitrogen-doped carbon photonic crystal (NCPC) with the ordered interconnected nanostructure is used in the electrode to prove the concept. NCPC can provide a fast charge transfer rate along the thickness direction and a uniform distribution for electrons and lithium ions, resulting in diminishing the concentration polarization and concentration gradient. When NCPC works for lithium-sulfur battery, the thick electrode achieves a fast charge transfer rate and a small voltage gap as well as the thin electrode. The 200 µm thick sulfur cathode obtains a specific capacity (87%) as high as 100 µm thick sulfur cathode. In contrast, the capacity ratio of the electrode made by the traditional coating method is only 45%.

9.
ACS Appl Mater Interfaces ; 13(35): 41744-41752, 2021 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-34436849

RESUMEN

Constructing a stable non-dendritic lithium metal anode is the key to the development of high-energy batteries in the future. Herein, we fabricated nitrogen-doped carbon photonic crystals in situ in the macropores of carbon papers as a porous skeleton and confined hosts for metallic lithium. The large specific surface area of the carbon photonic crystal reduces the current density of the electrode. The three-dimensional ordered microstructure promotes uniform charge distribution and uniform lithium deposition and inhibits the volume expansion of metallic lithium. The as-prepared lithium metal anode exhibits prominent electrochemical performance with a small hysteresis of less than 95 mV beyond 180 cycles at an extremely high current density of 15 mA cm-2. When the as-prepared lithium metal anode is coupled with the sulfur cathode, the obtained full cell displays enhanced capacitive properties and cycle life. Compared with the bare Li anode, the full cell exhibits more than 300 cycles of cell life and a 70 mA h g-1 higher discharge capacity.

10.
ACS Appl Mater Interfaces ; 13(8): 9955-9964, 2021 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-33606509

RESUMEN

Lithium-selenium (Li-Se) batteries suffer from the problems of polyselenides dissolution and volume expansion of active materials during the charge/discharge process. Moreover, the heavy atomic mass of selenium atoms limits the capacitive property of a Li-Se battery. Porous materials as the host for selenium particles reported by previous research studies are often disordered in pore structure and nonuniform in pore size. Herein, we report that a three-dimensional (3D) nitrogen-doped carbon photonic crystal (NCPC) with an ordered, interconnected structure was synthesized via a simple method to be the host of active materials. In addition, we prepared a Se-rich Se1-xSx by introducing a small amount of sulfur into a selenium ring to reduce the molecular mass but still keep the high electronic conductivity. As cathodes for a Li-Se battery, amorphous Se-rich Se1-xSx@NCPC composites exhibited high electrochemical performance with a specific capacity of 692 mA h g-1 at 0.1 Ag1-, an excellent rate capability of 526 mA h g-1 at 3 Ag1-, and an outstanding cycling property with an ultralow decay rate of 0.0132% per cycle at 0.6 Ag1- over 1000 cycles. Moreover, the pouch cell of Se1-xSx@NCPC composites also showed a good property with an energy of 253 Wh kg-1 at 0.1 Ag1- and an outstanding rate energy of 192 Wh kg-1 at 1.5 Ag1-, manifesting great potential in practical application.

11.
Nat Biomed Eng ; 4(11): 1063-1075, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33159193

RESUMEN

The systemic biodistribution of endogenous extracellular vesicles is central to the maintenance of tissue homeostasis. Here, we show that angiogenesis and heart function in infarcted heart tissue can be ameliorated by the local accumulation of exosomes collected from circulation using magnetic nanoparticles. The nanoparticles consist of a Fe3O4 core and a silica shell that is decorated with poly (ethylene glycol) conjugated through hydrazone bonds to two types of antibody, which bind either to CD63 antigens on the surface of extracellular vesicles or to myosin-light-chain surface markers on injured cardiomyocytes. On application of a local magnetic field, accumulation of the nanoparticles and cleavage of the hydrazone bonds under the acidic pH of injured cardiac tissue lead to the local release of the captured exosomes. In rabbit and rat models of myocardial infarction, the magnetic-guided accumulation of captured CD63-expressing exosomes in infarcted tissue led to reductions in infarct size as well as improved left-ventricle ejection fraction and angiogenesis. The approach could be used to manipulate endogenous exosome biodistribution for the treatment of other diseases.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Exosomas/química , Nanopartículas Magnéticas de Óxido de Hierro/administración & dosificación , Nanopartículas Magnéticas de Óxido de Hierro/química , Infarto del Miocardio/prevención & control , Animales , Anticuerpos/administración & dosificación , Anticuerpos/química , Femenino , Corazón/efectos de los fármacos , Ensayo de Materiales , Neovascularización Patológica/prevención & control , Ratas Sprague-Dawley , Distribución Tisular
12.
Nanotechnology ; 31(50): 505602, 2020 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-33006324

RESUMEN

A novel graphene nanoplatelets (GNP) bridge between two semiconductors (AgBr and graphitic carbon nitride) was created to boost photoelectrochemical performance. The heterojunction created makes the whole system a Z-scheme catalyst. For the construction of this catalyst, the syringe pump methodology was adopted and different analytical techniques were used for the confirmation of structure and morphology. High angle annular dark field (HAADF), dark field (DF), DF-4 and DF-2 techniques, using Z-contrast phenomena, confirmed the heterostructure (ABGCN) and its composition. The constructed structure showed an enhanced photoelectrochemical and catalytic property against 'acute toxicity category-III (MM)' and 'category-IV (tetracycline hydrochloride (TH))' organic pollutants. The constructed catalyst degraded the MM in 57 min and the TH in 35 min with degradation rates of 0.01489 min-1 and 0.02387 min-1, respectively, due to the accumulation of photogenerated electrons on the conduction band (CB) of g-C3N4 and photogenerated holes on the valence band (VB) of AgBr by the transformation of charges through the graphene bridge. An ion trapping study also revealed that ·O2 and h+ were the active species which actively participated in the photocatalytic reaction.

13.
Small ; 16(32): e2002518, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32613740

RESUMEN

Freestanding bifunctional electrodes with outstanding oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) properties are of great significance for zinc-air batteries, attributed to the avoided use of organic binder and strong adhesion with substrates. Herein, a strategy is developed to fabricate freestanding bifunctional electrodes from the predeposited nickel nanoparticles (Ni-NCNT) on carbon fiber paper. The steric effect of monodispersed SiO2 nanospheres limits the configuration of carbon atoms forming 3D interconnected nanotubes with uniformly distributed NiN2 active sites. The bifunctional electrodes (Ni-NCNT) demonstrate ideal ORR and OER properties. The zinc-air batteries assembled with Ni-NCNT directly exhibit extremely outstanding long term stability (2250 cycles with 10 mA cm-2 charge/discharge current density) along with high power density of 120 mV cm-2 and specific capacity of 834.1 mA h g-1 . This work provides a new view to optimize the distribution of active sites and the electrode structure.

14.
Sci Rep ; 9(1): 19364, 2019 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-31852935

RESUMEN

To propose an independent radiological index to evaluate surgical outcomes of A type basilar invagination, a retrospective study was conducted to compare the clinical outcome between procedures 1 and 2 by applying intraoperative consistent traction and manual reduction. Moreover, the atlantodental interval (ADI), cervicomedullary angle (CMA), bilateral sagittal inclination of atlantoaxial joint (SIAA) were measured and compared to pre-operation. Postoperatively, only these patients undergoing procedure 2 achieved significant neurological improvement. The ADIs and the SIAAs decreased in both groups, these differences are statistically significant between pre- and post- operation. For postoperative CMAs, only these patients undergoing modified surgery gained significant improvement of angle with mean 141°. We concluded that the CMA or SIAA could be a radiological predictor to evaluate surgical outcome in BI, among which the CMA is a more independent and easily measurable predictor that is closely correlated with satisfactory neurological improvements. Moreover, procedure 2 with intraoperative resistant cranial traction and manual reduction can help us achieve a good CMA.


Asunto(s)
Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/cirugía , Hueso Occipital/diagnóstico por imagen , Hueso Occipital/cirugía , Tomografía Computarizada por Rayos X , Adulto , Anciano , Articulación Atlantoaxoidea/diagnóstico por imagen , Articulación Atlantoaxoidea/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Hueso Occipital/patología , Periodo Posoperatorio , Resultado del Tratamiento
15.
ACS Nano ; 13(11): 13037-13046, 2019 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-31618012

RESUMEN

The nonuniformity of microscopic electrochemical reaction of electrodes essentially results in the partial reaction discrepancy and subsequent partial overheating, which is the most critical safety problem of the battery system in electric vehicles. Herein, we report a class of DLPC@S/DLPC@Li full cell based on a distinctly constructed double-layer photonic crystal (DLPC) with a three-dimensional-ordered interconnected structure. This full cell not only ensures the uniformity of microscopic electrochemical reaction but also solves common problems such as low conductivity of sulfur, poor cycle life, and lithium dendrite growth. Impressively, the full cell exhibits superior electrochemical performance pertaining to high reversible capacity of 703.3 mAh g-1 even at an extremely high rate of 10 C and excellent cycle performance with 1200 cycles with about 0.0317% capacity loss per cycle at 0.5 C.

16.
Nanotechnology ; 29(17): 175603, 2018 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-29446346

RESUMEN

Novel jujube-like hierarchical TiO2 microspheres (HTMs) were synthesized by an alkali-corrosion process of titanium phosphate (Ti2O3(H2PO4)2 · 2H2O) microspheres. The hierarchical titanium phosphate microsphere (HTPM) intermediates consisting of nanoflakes with a thickness of 20 nm were firstly prepared by a facile hydrothermal method. After reacting with diluted NaOH at low temperature and atmospheric pressure, followed by subsequent acid washing and a calcination process, the HTPM intermediates were transformed to TiO2 with the microsphere morphology well retained, while the nanoflakes became porous, and some new nanowires were formed between the nanoflakes. Finally, HTMs consisting of porous nanoflakes and nanowires were obtained. The possible growth mechanisms of HTPMs and HTMs are discussed. The HTMs demonstrate high specific surface area and excellent light-scattering ability. The performance of the dye sensitized solar cells (DSSCs) of the HTMs synthesized under different conditions is studied, and a total conversion efficiency of up to 8.93% was obtained. The improved DSSC performance was attributed to the enhanced dye loading, light-scattering, and charge transporting ability of the HTMs with a unique hierarchical nanostructure.

17.
Zhongguo Zhong Yao Za Zhi ; 42(13): 2524-2531, 2017 Jul.
Artículo en Chino | MEDLINE | ID: mdl-28840694

RESUMEN

Tianma(the tuber of Gastrodia eleta) is a widely used and pricy Chinese herb. Its counterfeits are often found in herbal markets, which are the plant materials with similar macroscopic characteristics of Tianma. Moreover, the prices of Winter Tianma(cultivated Tianma) and Spring Tianma(mostly wild Tianma) have significant difference. However, it is difficult to identify the true or false, good or bad quality of Tianma samples. Thus, a total of 48 Tianma samples with different characteristics(including Winter Tianma, Spring Tianma, slice, powder, etc.) and 9 plant species 10 samples of Tianma counterfeits were collected and analyzed by HPLC-DAD-MS techniques. After optimizing the procedure of sample preparation, chromatographic and mass-spectral conditions, the HPLC chromatograms of all those samples were collected and compared. The similarities and Fisher discriminant analysis were further conducted between the HPLC chromatograms of Tianma and counterfeit, Winter Tianma and Spring Tianma. The results showed the HPLC chromatograms of 48 Tianma samples were similar at the correlation coefficient more than 0.848(n=48). Their mean chromatogram was simulated and used as Tianma HPLC fingerprint. There were 11 common peaks on the HPLC chromatograms of Tianma, in which 6 main peaks were chosen as characteristic peaks and identified as gastrodin, p-hydroxybenzyl alcohol, parishin A, parishin B, parishin C, parishin E, respectively by comparison of the retention time, UV and MS data with those of standard chemical compounds. All the six chemical compounds are bioactive in Tianma. However, the HPLC chromatograms of the 10 counterfeit samples were significantly different from Tianma fingerprint. The correlation coefficients between HPLC fingerprints of Tianma with the HPLC chromatograms of counterfeits were less than 0.042 and the characteristic peaks were not observed on the HPLC chromatograms of these counterfeit samples. It indicated the true or false Tianma can be identified by either the similarity or characteristic peaks on HPLC fingerprint. Comparing the Winter Tianma with Spring Tianma showed that the HPLC chromatograms of 15 winter Tianma samples and 11 spring Tianma samples were similar at the mean correlation coefficient of 0.908. But the intensity of the characteristic peaks were different between the two groups of Tianma samples, i.e. the intensity of gastrodin, paishin A and C in winter Tianma was lower than those in spring Tianma. The Winter Tianma and Spring Tianma could be discriminated by either the Fisher unstandardized discrimination function or Linear discriminant function, based on the peak areas of 11 common peaks on HPLC chromatograms as variate.


Asunto(s)
Cromatografía Líquida de Alta Presión , Medicamentos Herbarios Chinos/normas , Gastrodia/química , Tubérculos de la Planta/química , Análisis Discriminante , Plantas Medicinales/química , Control de Calidad , Estaciones del Año
18.
Cell Reprogram ; 18(6): 411-418, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27906583

RESUMEN

Nuclei from less differentiated stem cells yield high cloning efficiency. However, pluripotent stem cells are rather difficult to obtain from bovines. Skin-derived precursor (SKPs) cells exhibit a certain degree of pluripotency, which has been shown to enhance the efficiency of nuclear transfer (NT) in pigs. In this study, bovine SKPs were isolated and characterized. Results showed that bovine SKPs expressed nestin, fibronectin, vimentin, pluripotency-related genes, and characteristic neural crest markers, such as NGFR, PAX3, SOX9, SNAI2, and OCT4. Bovine SKPs and fibroblasts were used as NT donor cells to examine and compare the preimplantation developmental potential of reconstructed embryos after somatic cell nuclear transfer (SCNT). Bovine SKP-cloned embryos displayed higher developmental competence in terms of blastocyst formation rate and total cell number in blastocysts compared with the bovine embryonic fibroblast-cloned embryos. This study revealed that bovine SKPs may be considered excellent candidate nuclear donors for SCNT and may provide a promising platform for transgenic cattle generation.


Asunto(s)
Blastocisto/citología , Embrión de Mamíferos/citología , Fibroblastos/citología , Técnicas de Transferencia Nuclear/veterinaria , Células Madre Pluripotentes/citología , Piel/citología , Animales , Blastocisto/fisiología , Bovinos , Diferenciación Celular , Separación Celular , Células Cultivadas , Embrión de Mamíferos/fisiología , Desarrollo Embrionario , Femenino , Fibroblastos/fisiología , Células Madre Pluripotentes/fisiología
19.
Cell Biol Int ; 40(5): 603-8, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26936441

RESUMEN

Macrophages, as the forefront of innate immune defense, have an important role in the host responses to mycobacterial infection. Therefore, a stable macrophage cell line is needed for future bovine immune system research on the bacterial infection. In this study, we established a bovine macrophage cell line by introducing the human telomerase reverse transcriptase (hTERT) gene into bovine bone marrow-derived macrophages (bBMMs). The TERT-bBMMs cells expressed macrophage surface antigen (CD11b, CD282) and upregulated expression of the cytokines IL-1ß, IL-6, IL-10, IL-12, TNF-α in response to bacterial invasion. These results demonstrate that this cell line provide reliable cell model system for future studies on interactions between the bovine macrophages and Mycobacterium tuberculosis.


Asunto(s)
Línea Celular , Macrófagos/citología , Animales , Bovinos , Citocinas/metabolismo , Humanos , Interleucinas/metabolismo , Macrófagos/metabolismo , Transducción de Señal , Telomerasa/biosíntesis , Telomerasa/genética , Factor de Necrosis Tumoral alfa/metabolismo
20.
Zhong Yao Cai ; 39(5): 980-5, 2016 May.
Artículo en Chino | MEDLINE | ID: mdl-30132631

RESUMEN

Objective: To assess the quality of Paeonia lactiflora roots by the multi-bioactive chemical markers. Methods: Total of66 Paeonia lactiflora roots samples were collected from Sichuan,Zhejiang and Anhui. An UHPLC-DAD technique was employed to quantify the contents of paeoniflorin,hydroypaeoniflorin,abiflorin,pentagalloyglucose,benzoypaeoni-florin,paeonol,gallic and catechin in these samples. These chemical components in each sample were also calculated by Principal Component Analysis( PCA). Results: The eight bioactive components were good separated in 30 min on the UHPLC chromatogram. The correlation coefficients between peak areas and concentration for these bioactive components were not less than 0. 9990( n = 6). And their recoveries were in the range of95. 94% ~ 100. 92%( n = 6). The contents of paeoniflorin in Paeonia lactiflora roots samples collected from Sichuan,Zhejiang and Anhui were 40. 54 mg / g( n = 23),33. 09 mg / g( n = 22) and 39. 47 mg / g( n = 21),respectively. The values of PCA were 0. 4435( n = 23)for the samples from Sichuan,0. 0122( n = 22) for the samples from Zhejiang and- 4. 9850( n = 21) for the samples from Anhui. The content of paeoniflorin in biennial,triennial,four-year,five-year and six-year old Paeonia lactiflora roots were 24. 76( n = 2),37. 17( n= 16),37. 83( n = 23),39. 71( n = 16) and 37. 45 mg / g( n = 7),respectively. Conclusion: The developed method can accurately quantify the content of principal bioactive compounds in Paeonia lactiflora roots. The quality is various among Paeonia lactiflora roots cultivated in Sichuan, Zhejiang and Anhui on the basis of paeoniflorin content or the value of PCA,but the quality of Paeonia lactiflora roots cultivated in Sichuan is the best. Moreover, it is suggested Paeonia lactiflora roots should be harvested in third or fourth year based on the output and quality.


Asunto(s)
Cromatografía Líquida de Alta Presión , Paeonia , Acetofenonas , Medicamentos Herbarios Chinos , Glucósidos , Monoterpenos , Raíces de Plantas
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