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1.
Molecules ; 27(21)2022 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-36364192

RESUMEN

Metabolomics is an essential method to study the dynamic changes of metabolic networks and products using modern analytical techniques, as well as reveal the life phenomena and their inherent laws. Currently, more and more attention has been paid to the development of metabolic histochemistry in the fungus field. This paper reviews the application of metabolomics in fungal research from five aspects: identification, response to stress, metabolite discovery, metabolism engineering, and fungal interactions with plants.


Asunto(s)
Redes y Vías Metabólicas , Metabolómica , Metabolómica/métodos , Plantas
2.
Nat Prod Res ; 36(8): 1988-1995, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33153339

RESUMEN

Three new steroidal glycosides, metapregnoside A-C (II-IV), together with one known compound, byzantionoside B (I), were isolated from the fresh whole herb of Metaplexis japonica by using high-speed countercurrent chromatography and semi-preparative liquid chromatography. Their structures and relative configurations were elucidated by spectroscopic methods including 1D NMR, 2D NMR and HR-ESI-MS. The potential targets of compound I-IV were identified by virtual screening. And the potential inhibitory effects of these compounds on tyrosine protein kinases were compared by molecular docking. Byzantionoside B (I) was the first isolated compound from Metaplexis genus. The docking score of metapregnoside C (IV) was the highest. And the sugar chain residues at position C-20 in the pregn-4-en-3-one derivatives is the main factor affecting their docking scores on tyrosine protein kinases Fes/Fps.


Asunto(s)
Apocynaceae , Cynanchum , Apocynaceae/química , Cynanchum/química , Glicósidos/química , Simulación del Acoplamiento Molecular , Estructura Molecular , Proteínas Tirosina Quinasas
3.
Front Pharmacol ; 12: 731847, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34603047

RESUMEN

COVID-19 pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has ravaged the world, resulting in an alarming number of infections and deaths, and the number continues to increase. The pathogenesis caused by the novel coronavirus was found to be a disruption of the pro-inflammatory/anti-inflammatory response. Due to the lack of effective treatments, different strategies and treatment methods are still being researched, with the use of vaccines to make the body immune becoming the most effective means of prevention. Antiviral drugs and respiratory support are often used clinically as needed, but are not yet sufficient to alleviate the cytokine storm (CS) and systemic inflammatory response syndrome. How to neutralize the cytokine storm and inhibit excessive immune cell activation becomes the key to treating neocoronavirus pneumonia. Immunotherapy through the application of hormones and monoclonal antibodies can alleviate the immune imbalance, but the clinical effectiveness and side effects remain controversial. This article reviews the pathogenesis of neocoronavirus pneumonia and discusses the immunomodulatory therapies currently applied to COVID-19. We aim to give some conceptual thought to the prevention and immunotherapy of neocoronavirus pneumonia.

4.
J Chromatogr A ; 1629: 461426, 2020 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-32858452

RESUMEN

Selecting the appropriate solvent system is the key to the successful separation of samples by using countercurrent chromatography. Although high-speed countercurrent chromatography has been widely used in the separation and preparation of natural products, the selection of a solvent system has always been a stumbling block to the application of high-speed countercurrent chromatography. In order to explore a rapid and practical prediction method to select countercurrent chromatography solvent system, five linear prediction models of the Arizona solvent system family (HEMW) was established by using fourteen compounds with different structures and five HPLC columns of different brands. And two different solvent system selection methods (The partition coefficient K of the target compound in the solvent system was in the range of 0.25 < K < 2.5) were proposed for targeted separation of compounds and multi-component separation in a complex sample respectively. The appropriate HSCCC solvent system of five known compounds was determined by a HPLC analysis and a shake flask test and the appropriate HSCCC solvent system of two Chinese herbal extracts was determined by a HPLC analysis to verify the prediction method. In this study, solid-liquid partition chromatography (HPLC) and liquid-liquid partition chromatography (HSCCC) were linked by polarity to simplify the screening process of solvent system. This method reduced the difficulty and workload of solvent system selection, which provided methods and ideas for more solvent system prediction models.


Asunto(s)
Distribución en Contracorriente/métodos , Solventes/química , Arizona , Cromatografía Líquida de Alta Presión , Metanol/química , Modelos Teóricos , Estándares de Referencia
5.
Anal Chim Acta ; 1109: 130-139, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32252896

RESUMEN

A novel three-dimensional nickel hydroxide/polyurethane (Ni(OH)2/PU) electrode was prepared by a simple and environmentally friendly method and used for non-enzymatic detection of glucose. The Ni(OH)2/PU electrode was obtained by one-pot hydrothermal method of loading nickel hydroxide on a cheap, easily available and flexible polyurethane sponge, which is facile and energy-saving. The porous structure of the polyurethane sponge provides a large surface area and a rich electrochemical active site for the electrode, which is beneficial to the oxidation reaction of glucose on the surface of the electrode with Ni(OH)2. The Ni(OH)2/PU electrode structure was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The cyclic voltammetry test was used to study the catalytic performance of Ni(OH)2/PU electrode for oxidation of glucose and the chronoamperometry was used to investigate the detection performance of Ni(OH)2/PU electrode on glucose. The results indicate that this non-enzymatic glucose sensor had a high sensitivity of 2845 µA mM-1 cm-2, a low detection limit of 0.32 µM (S/N = 3), a detection range of 0.01-2.06 mM and response time of less than 5 s. In addition, the Ni(OH)2/PU electrode had excellent selectivity, reproducibility and stability and also exhibited effective detection of glucose in fetal bovine serum (FBS). In summary, Ni(OH)2/PU electrode had broad prospects as an excellent candidate for non-enzymatic glucose sensors. The study also opens up a facile and energy-saving approach for preparing three-dimensional (3D) functionalized polymer electrode via hydrothermal method as electrochemical sensors.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Glucosa/análisis , Hidróxidos/química , Níquel/química , Poliuretanos/química , Electrodos
6.
Artículo en Inglés | MEDLINE | ID: mdl-32308721

RESUMEN

OBJECTIVE: Influenza virus poses a major threat to human health and has serious morbidity and mortality which commonly occurs in high-risk populations. Pharynx and larynx of the upper respiratory tract mucosa is the first defense line against influenza virus infection. However, the ability of the pharynx and larynx organ to eliminate the influenza pathogen is still not clear under different host conditions. METHODS: In this study, a mouse model of kidney yang deficiency syndrome (KYDS) was used to mimic high-risk peoples. Two different methods of influenza A (H1N1) virus infection by nasal dropping or tracheal intubation were applied to these mice, which were divided into four groups: normal intubation (NI) group, normal nasal dropping (ND) group, model intubation (MI) group, and model nasal dropping (MD) group. The normal control (NC) group was used as a negative control. Body weight, rectal temperature, and survival rate were observed every day. Histopathologic changes, visceral index, gene expressions of H1N1, cytokine expressions, secretory IgA (SIgA) antibodies of tracheal lavage fluids in the upper respiratory tract, and bronchoalveolar lavage fluids were analyzed by ELISA. RESULTS: The MD group had an earlier serious morbidity and mortality than the others. MI and NI groups became severe only in the 6th to 7th day after infection. The index of the lung increased significantly in NI, MI, and MD groups. Conversely, indices of the thymus and spleen increased significantly in NC and ND groups. H&E staining showed severe tissue lesions in MD, MI, and NI groups. H1N1 gene expressions were higher in the MD group compared with the MI group on the 3rd day; however, the MD group decreased significantly on the 7th day. IL-6 levels increased remarkably, and SIgA expressions decreased significantly in the MD group compared with the NC group. CONCLUSIONS: SIgA secretions are influenced directly by different conditions of the host in the pharynx and larynx in the upper respiratory tract mucosa. In the KYDS virus disease mode, SIgA expressions could be inhibited severely, which leads to serious morbidity and mortality after influenza A virus infection. The SIgA expressions of the pharynx and larynx would be an important target in high-risk populations against the influenza A virus for vaccine or antiviral drugs research.

7.
ACS Appl Mater Interfaces ; 12(1): 934-944, 2020 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-31829553

RESUMEN

The electrocatalytic applications of traditional polyimide film and carbon nanomaterials are hindered due to a shortage of three-dimensional hierarchical conductivity and porous structure. Herein, a novel polyimide-based electrode based on a highly efficient palladium nanocatalyst embellished three-dimensional reduced graphene oxide/polyimide foam (Pd/3D RGO@PI foam, signed PRP) toward H2O2 electroreduction was designed and prepared through thermal foaming procedure, followed by facile dip-drying method and electrodeposition. As expected, such a binder-free, 3D hierarchical structure PRP electrode presented high catalytic property, good stability, as well as low activation energy toward H2O2 electroreduction during the electrochemical measurement period. The PRP electrode showed a reduction current density of 810 mA·cm-2 at -0.2 V (vs Ag/AgCl) in 2.0 mol·L-1 H2SO4 and 2.0 mol·L-1 H2O2. Moreover, the PRP electrode also illustrated good reproducibility and repeatability. Reproducibility presented almost 95.8% of the initial current density after 1000 cycles test. Also, the activation energy of H2O2 electroreduction on 3D PRP electrode was 21.624 kJ·mol-1. Benefiting from the 3D hierarchical structure and efficient catalyst, the PRP electrode exhibited excellent electrocatalytic performance and was considered to be a potential candidate material for fuel cells.

8.
Int J Biol Macromol ; 128: 724-731, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-30703419

RESUMEN

A new polysaccharide named GRP (Glehniae radix polysaccharide) was isolated and purified from Glehniae radix by hot water extraction, ethanol precipitation, anion-exchange and gel-filtration chromatography. GRP was homogeneous, with a molecular weight of 1.33×104Da, as determined by high-performance size-exclusion chromatography-refractive index detector analysis. Its structural characteristics were investigated and elucidated by methylation analysis, gas chromatography mass spectrometry, Fourier transform infrared and nuclear magnetic resonance spectroscopy. Based on obtained data, GRP was found to be α­d­glucan containing (1→6)-linked and (1→3)-linked backbone with a branch of one (1→6)-linked and terminal glucoses submitting at the C-4 position every fourteen residues. The biological activities of GRP upon proliferation of splenic lymphocyte, RAW264.7 cells and A549 cell, and production of nitric oxide (NO) were investigated in vitro. The results showed that GRP exhibited inhibition against A549 cells proliferation and NO production in RAW264.7 cells, and displayed promotion for proliferation of mouse spleen lymphocytes and RAW264.7 cells, which suggested that GRP may have potential immunoregulation, anti-inflammatory and anti-tumor activity.


Asunto(s)
Apiaceae/química , Polisacáridos/química , Polisacáridos/farmacología , Agua/química , Células A549 , Animales , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/farmacología , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Humanos , Factores Inmunológicos/química , Factores Inmunológicos/aislamiento & purificación , Factores Inmunológicos/farmacología , Linfocitos/citología , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Ratones , Monosacáridos/análisis , Óxido Nítrico/biosíntesis , Polisacáridos/aislamiento & purificación , Células RAW 264.7 , Solubilidad , Bazo/inmunología
9.
Artículo en Inglés | MEDLINE | ID: mdl-30554094

RESUMEN

A simple, sensitive and selective high-performance liquid chromatography electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) method was developed and validated for simultaneous determination and pharmacokinetic study of 15 active compounds (Saikosaponin A, Baicalin, Wogonin, Glycyrrhizic acid, Glycyrrhetinic acid, Albiflorin, Paeoniflorin, Liquiritin, Isoliquiritin, Liquiritigenin, Isoliquiritigenin, Cinnamic acid, Gallic acid, Wogonoside and Oroxylin A) in rat plasma. After a feasible protein precipitation using methanol for sample preparation, chromatographic separation was carried out with a Halo® C18 column (2.1 × 100 mm, 2.7 µm) at 35 °C, water containing 0.1% formic acid and acetonitrile were used as the mobile phase with a flow rate of 0.3 mL/min. Multiple reaction monitoring (MRM) with positive and negative ion switching mode was performed for the quantification of the standards and internal standard in plasma. All the calibration curves showed good linear regression within the linear range (r2 > 0.9923). In particular, the results of the method validation including specificity, linearity, accuracy, precision, extraction recovery, matrix effect, and stability of compounds in bio-samples were all within the current acceptance criteria. The established method was successfully applied to the pharmacokinetic study of 15 compounds in rats after oral administration of CGD and laid the foundation for studying the active components and mechanism of CGD in vivo.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/análisis , Medicamentos Herbarios Chinos/farmacocinética , Espectrometría de Masas en Tándem/métodos , Animales , Medicamentos Herbarios Chinos/química , Flavanonas/sangre , Flavanonas/química , Flavanonas/farmacocinética , Ácido Gálico/sangre , Ácido Gálico/química , Ácido Gálico/farmacocinética , Glucósidos/sangre , Glucósidos/química , Glucósidos/farmacocinética , Límite de Detección , Modelos Lineales , Ratas , Ratas Sprague-Dawley , Reproducibilidad de los Resultados , Saponinas/sangre , Saponinas/química , Saponinas/farmacocinética
10.
Photodiagnosis Photodyn Ther ; 23: 35-39, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29800714

RESUMEN

BACKGROUND: We previously reported that pheophorbide a (PhA), excited by 630 nm light, significantly inhibited the growth of prostate cancer cells. In this study, we employed whole-cell proteomics to investigate photodynamic treatment (PDT)-related proteins. METHODS: Two-dimensional gel electrophoresis (2-DE) coupled with tandem mass spectrometry was employed to reveal the proteins involved in PhA-mediated PDT in LNCaP and PC-3 prostate cancer cells. RESULTS: After PhA-PDT treatment, decreased expression of translationally-controlled tumor protein (TCTP) was found in both PC-3 and LNCaP whole-cell proteomes. In contrast, human rab GDP dissociation inhibitor (GDI) in LNCaP cells and ras-related homologs GDI in PC-3 cells were up-regulated. CONCLUSIONS: GDP-GTP exchange is an underlying target of photodynamic treatment in prostate cancer cells.


Asunto(s)
Clorofila/análogos & derivados , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , Proteómica/métodos , Línea Celular Tumoral , Clorofila/farmacología , Guanosina Difosfato/metabolismo , Guanosina Trifosfato/metabolismo , Humanos , Masculino , Células PC-3 , Neoplasias de la Próstata/patología , Espectrometría de Masas en Tándem , Proteína Tumoral Controlada Traslacionalmente 1 , Electroforesis Bidimensional Diferencial en Gel , Proteínas ras/metabolismo
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