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1.
Antonie Van Leeuwenhoek ; 111(7): 1237-1257, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29397489

RESUMEN

Accumulated evidence suggests that root exudates have a major role in mediating plant-microbe interactions in the rhizosphere. Here, we characterized tobacco root exudates (TREs) by GC-MS and nicotine, scopoletin, and octadecane were identified as three main components of TREs. Qualitative and quantitative chemotaxis assays revealed that Pseudomonas aeruginosa NXHG29 with antagonistic activity displayed positive chemotactic responses towards TREs and their three main components (nicotine, scopoletin, octadecane) and its enhanced chemotaxis were induced by these substances in a concentration-dependent manner. Furthermore, following GC-MS and chemotaxis analysis, nicotine was selected as the target for evaluation of the effect on NXHG29 regarding antagonism, growth, root colonization and biocontrol efficiency. Results of in vitro studies showed that nicotine as a sole carbon source could enhance growth of NXHG29 and significantly increased the antagonism of NXHG29. We also demonstrated that nicotine exerted enhancing effects on the colonization ability of NXHG29 on tobacco roots by combining CLSM observations with investigation of population level dynamics by selective dilution plating method. Results from greenhouse experiments suggested nicotine exhibited stimulatory effects on the biocontrol efficiency of NXHG29 against bacterial wilt and black shank on tobacco. The stimulatory effect of nicotine was affected by the concentration and timing of nicotine application and further supported by the results of population level of NXHG29 on tobacco roots. This is the first report on the enhancement effect of nicotine from TREs on an antagonistic bacterium for its root colonization, control of soil-borne pathogens, regarding the chemotaxis and in vitro antagonism and growth.


Asunto(s)
Quimiotaxis/efectos de los fármacos , Nicotiana/química , Nicotina/farmacología , Exudados de Plantas/farmacología , Pseudomonas aeruginosa/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas , Nicotina/química , Nicotina/aislamiento & purificación , Enfermedades de las Plantas/microbiología , Exudados de Plantas/química , Exudados de Plantas/aislamiento & purificación , Raíces de Plantas/química , Pseudomonas aeruginosa/crecimiento & desarrollo , Pseudomonas aeruginosa/fisiología
2.
Int J Syst Evol Microbiol ; 67(10): 3699-3705, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28879837

RESUMEN

A Gram-stain-positive, rod-shaped, motile bacterium, designated as 1404T, was isolated from leaves of Chinese red pepper (Huajiao) (Zanthoxylum bungeanum Maxim) collected from Gansu, north-west China. Spores were not observed under a range of conditions. Strain 1404T was observed to grow at 15-45 °C and pH 6.0-10.0 and in presence of 0-5 % (w/v) NaCl concentration. The cell wall of strain 1404T was found to contain meso-diaminopimelic acid, and the predominant respiratory quinone was identified as MK-7. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and an unidentified phospholipid as well as three unidentified polar lipids. The major fatty acids profile of strain 1404T consisted of iso-C15 : 0 (25.6 %), anteiso-C15 : 0 (18.4 %) and iso-C14 : 0 (12.1 %). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 1404T was affiliated to the genus Bacillus and was closely related to Bacillusoryzisoli 1DS3-10T, Bacillusbenzoevorans DSM 5391T and Bacilluscirculans DSM 11T with sequence similarity of 98.3, 98.2 and 96.9 %, respectively. The G+C content of the genomic DNA was determined to be 39.4 mol%. DNA-DNA hybridization values indicated that relatedness between strain 1404T and the type strains of closely related species of the genus Bacillus was below 41 %. Therefore, on the basis of the data from the polyphasic taxonomic study presented, strain 1404T represents a novel species of the genus Bacillus, for which the name proposed is Bacillus endozanthoxylicus sp. nov. The type strain is 1404T (=CCTCC AB 2017021T=KCTC 33827T).


Asunto(s)
Bacillus/clasificación , Filogenia , Hojas de la Planta/microbiología , Zanthoxylum/microbiología , Bacillus/genética , Bacillus/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , Pared Celular/química , China , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Hibridación de Ácido Nucleico , Peptidoglicano/química , Fosfatidilgliceroles/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Microbiología del Suelo , Vitamina K 2/análogos & derivados , Vitamina K 2/química
3.
Phytother Res ; 30(10): 1572-1583, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27373780

RESUMEN

The entomopathogenic fungus Ophiocordyceps sinensis, formerly known as Cordyceps sinensis, has long been used as a traditional Chinese medicine for the treatment of many illnesses. In recent years its usage has increased dramatically because of the improvement of people's living standard and the emphasis on health. Such demands have resulted in over-harvesting of this fungus in the wild. Fortunately, scientists have demonstrated that artificially cultured and fermented mycelial products of O. sinensis have similar pharmacological activities to wild O. sinensis. The availability of laboratory cultures will likely to further expand its usage for the treatment of various illnesses. In this review, we summarize recent results on the pharmacological activities of the components of O. sinensis and their putative mechanisms of actions. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Cordyceps/química , Medicina Tradicional China/métodos
4.
RSC Adv ; 14(26): 18367-18372, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38854837

RESUMEN

The rational design and facile preparation of a catalyst with high activity, strong durability and low consumption for the oxygen evolution reaction (OER) is an ongoing challenge in water splitting to generate clean and renewable H2 fuel. Herein, bimetallic metal-organic frameworks (MOFs) with a uniform morphology, controlled metal ratio and low crystallinity were constructed using a simple and reliable one-step solvothermal method. The three-dimensional (3D) flower-like MOF (F-Ni1Co4-BTC) with a Ni to Co molar ratio of 1 : 4 coordinated with 1,3,5-benzenetricarboxylic acid exhibited excellent OER catalytic activity compared with its corresponding counterparts, which can be attributed to the establishment of the exquisite morphology, the proportion of the dual-metal center, and the formation of active intermediates. Furthermore, when F-Ni1Co4-BTC was directly grown on carbon cloth (F-Ni1Co4-BTC/CC), it achieved an obvious improvement in electrochemical performance, affording a low overpotential of 292 mV at a current density of 10 mA cm-2, a small Tafel slope (48 mV dec-1), and excellent mechanical durability in an alkaline electrolyte, which is due to the integrated electrode attained richer active sites and faster electron transfer rate with the introduction of highly conductive carbon cloth. Our work offers a promising strategy to tailor the properties of bimetallic MOFs and the possibility of highly efficient earth-abundant catalysts for practical applications.

5.
Reprod Toxicol ; 129: 108671, 2024 10.
Artículo en Inglés | MEDLINE | ID: mdl-39038764

RESUMEN

Maternal prenatal hypoxia is an important contributor to intrauterine growth restriction (IUGR), which impedes fetal lung maturation and leads to the development of chronic lung diseases. Although evidence suggests the involvement of pyroptosis in IUGR, the molecular mechanism of pyroptosis is still unclear. Nuclear factor erythroid 2-related factor 2 (Nrf2) has been found to potentially interact with gasdermin D (GSDMD), the key protein responsible for pyroptosis, indicating its crucial role in inhibiting pyroptosis. Therefore, we hypothesized that Nrf2 deficiency is a key molecular responsible for lung pyroptosis in maternal hypoxia-induced IUGR offspring mice. Pregnant WT and Nrf2-/- mice were exposed to hypoxia (10.5 % O2) to mimic IUGR model. We assessed body weight, lung histopathology, pulmonary angiogenesis, oxidative stress levels, as well as mRNA and protein expressions related to inflammation in the 2-week-old offspring. Additionally, we conducted a dual-luciferase reporter assay to confirm the targeting relationship between Nrf2 and GSDMD. Our findings revealed that offspring with maternal hypoxia-induced IUGR exhibited reduced birth weight, catch-up growth delay, and pulmonary dysplasia. Furthermore, we observed impaired nuclear translocation of Nrf2 and increased GSDMD-mediated pyroptosis in these offspring with IUGR. Moreover, the dual-luciferase reporter assay demonstrated that Nrf2 could directly inhibit GSDMD transcription; deficiency of Nrf2 exacerbated pyroptosis and pulmonary dysplasia in offspring with maternal hypoxia-induced IUGR. Collectively, our findings suggest that Nrf2 deficiency induces GSDMD-mediated pyroptosis and pulmonary dysplasia in offspring with maternal hypoxia-induced IUGR; thus highlighting the potential therapeutic approach of targeting Nrf2 for treating prenatal hypoxia-induced pulmonary dysplasia in offspring.


Asunto(s)
Retardo del Crecimiento Fetal , Hipoxia , Pulmón , Ratones Endogámicos C57BL , Ratones Noqueados , Factor 2 Relacionado con NF-E2 , Piroptosis , Animales , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Embarazo , Femenino , Hipoxia/complicaciones , Pulmón/patología , Pulmón/metabolismo , Ratones , Proteínas de Unión a Fosfato/metabolismo , Proteínas de Unión a Fosfato/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Efectos Tardíos de la Exposición Prenatal , Masculino , Estrés Oxidativo , Gasderminas
6.
RSC Adv ; 13(31): 21296-21299, 2023 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-37456544

RESUMEN

Compounds PTZ-MBZ (methyl 3-(10H-phenothiazin-10-yl)benzoate) and DMAC-MBZ (methyl 3-(9,9-dimethylacridin-10(9H)-yl)benzoate) were conveniently synthesized, and they exhibited TADF properties with lifetimes of 0.80 and 2.17 µs, respectively. The spatially separated highest occupied molecular orbital and lowest unoccupied molecular orbital resulted in a very small singlet-triplet energy gap of 0.0152 eV and 0.0640 eV, respectively. Thermally activated delayed fluorescence materials with short lifetime could be used as promising luminescent materials for organic light-emitting diodes.

7.
Ying Yong Sheng Tai Xue Bao ; 33(6): 1547-1554, 2022 Jun.
Artículo en Zh | MEDLINE | ID: mdl-35729132

RESUMEN

Fire is an important influencing factor in forest ecosystems. Establishing an accurate forest fire forecasting model is important for forest fire management. We used different meteorological factors as predictors to construct a forest fire prediction model in Fujian Province, based on Logistic regression and generalized linear mixed effect model. We compared the fitness and prediction accuracy of the two models, judged the applicability of the mixed effect model in forest fire forecasting. The results showed that the AUC and accuracy values of the Logistic base model were 0.664 and 60.4%, respectively. Models considering random effects gave better fitting and validating statistics. Among them, the two-level mixed model containing both area and altitude difference effects performed best, with increases of 0.057 and 6.0% for the AUC and accuracy values, respectively. By applying the model to predict the probability of forest fires in Fujian Province, we found that the middle-incidence and high-incidence areas of forest fires distributed in northwest and south Fujian, whereas the low-incidence areas of forest fires distributed in southwest and east Fujian, which was consistent with the observed data. The data fitting and forest fire prediction of the mixed effects model was better than those of the Logistic basic model. Therefore, it could be used as an important tool for forest fire prediction and management.


Asunto(s)
Incendios , Incendios Forestales , Ecosistema , Predicción , Bosques
8.
Ying Yong Sheng Tai Xue Bao ; 32(1): 134-144, 2021 Jan.
Artículo en Zh | MEDLINE | ID: mdl-33477221

RESUMEN

Constructions of process or mechanistic models are limited by physiological parameters, due to difficulty in direct and precise measurement. Global sensitivity analysis could evaluate the response of model outputs to changes in physiological parameters, and provide information for improving model structure, data collection, and parameter calibration. Based on a process model CROBAS, 10 parameters related to tree structure of Pinus armandii were selected to compare three widely used global sensitivity analysis methods (the Morris screening method, the variance-based Sobol indices, and the Extended Fourier Amplitude Sensitivity Test (EFAST)), with the objective function formulated by the Nash-Sutcliffe Efficiency (NSE) of tree height and biomass. The results showed that the sensitivity order of parameters slightly varied across different methods, which considerably changed with different objective functions. Both the Morris method and the EFAST method outperformed the Sobol method in terms of time consuming and convergence efficiency. All outputs were sensitive to the maximum rate of canopy photosynthesis per unit area, the specific leaf area, and the extinction coefficient. The light interception of tree canopy played a key role in the simulation of tree growth with CROBAS, suggesting that the module of photosynthetic carbon fixation took priority over any other modules for data collection and model validation during module calibration and tree growth simulation for CROBAS. The calculation and validation of foliage biomass module were crucial when applying carbon balance theory to biomass simulations. In conclusion, for the sensitivity analysis of a complex process-based model, the Morris method was suitable for qualitative studies, while the EFAST method was recommended for quantitative studies.


Asunto(s)
Fotosíntesis , Pinus , Biomasa , Carbono , Hojas de la Planta
9.
Bioelectrochemistry ; 131: 107396, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31704455

RESUMEN

We report a novel chiral interface based on polysaccharides that was integrated via an amidation reaction between the COOH of sodium alginate and the NH2 of chitosan to form a chiral selector (SA-CS) with three dimensional N-doped graphene-CNT (NGC) as the substrate material. This interface was used for chiral discrimination of tryptophan (Trp) enantiomers via electrochemical measurements. The FT-IR, SEM, TEM and XPS characterization showed that the chiral selector and substrate materials were prepared successfully. Compared with individual SA-CS and NGC, the integrated polysaccharides/3D NGC showed higher enantioselectivity for L-Trp than D-Trp due to the smaller steric hindrance for D-Trp during the formation of three-point interactions between the two diastereoisomeric enantiomer-selector complexes, which allowed L-Trp to more easily detach from the electrode modification layer and approach the electrode surface, facilitating its approach and confirming that SA-CS had a higher constant for L-Trp when applied to real samples.


Asunto(s)
Técnicas Electroquímicas/métodos , Grafito/química , Nitrógeno/química , Polisacáridos/química , Estereoisomerismo , Termodinámica
10.
Bioelectrochemistry ; 128: 74-82, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30933903

RESUMEN

Graphene oxide (GO) modified with ferrocene (Fc) was successfully assembled via the π-π interaction (GO-Fc) and had the features of large surface area and high loading. Then, a novel composite was synthesized via ß-cyclodextrin (ß-CD) functionalized GO-Fc by combining the advantages of GO-Fc and ß-CD. An efficient chiral electrochemical sensing interface was constructed by using the rGO-Fc-CD composite as the electrode modification for the recognition of phenylalanine (Phe) enantiomers. The successful synthesis of the composites was confirmed by FTIR, XRD, TGA, SEM, and XPS results. The host-guest inclusion interaction was detected by ultraviolet spectroscopy and DPV. The recognition results demonstrated that the rGO-Fc-CD/GCE showed a higher chiral recognition capability for L-Phe than for D-Phe. The enantioselectivity coefficient (ID/IL) of the proposed sensor was 2.47. The LOD values of 27 nM and 52 nM (S/N = 3) for L-Phenylalanine and D-Phenylalanine were obtained for this electrochemical sensor. The as-synthesized material was successfully exploited for the recognition of Phe enantiomers, indicating that the developed sensor has wide application prospects.


Asunto(s)
Ciclodextrinas/química , Técnicas Electroquímicas/métodos , Compuestos Ferrosos/química , Grafito/química , Metalocenos/química , Electrodos , Límite de Detección , Microscopía Electrónica de Rastreo , Fenilalanina/análisis , Fenilalanina/química , Espectroscopía de Fotoelectrones , Espectroscopía Infrarroja por Transformada de Fourier , Estereoisomerismo , Termogravimetría , Difracción de Rayos X
11.
Oncol Rep ; 40(5): 2826-2835, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30226624

RESUMEN

A number of studies has shown that long non-coding RNAs (lncRNAs), microRNAs (miRNAs) and protein coding genes (PCGs) are involved in various pathophysiological processes and can be used as prognostic biomarkers in cancer patients. The purpose of this study was to find a multidimensional transcriptome signature to predict clinical outcomes in bladder cancer. Using Cox's proportional hazards regression analysis and the random survival forest algorithm, we mined the expression profile data of 239 bladder cancer patients derived from The Cancer Genome Atlas (TCGA) public database. A signature comprised of two PCGs (ACADS and C1QTNF9B), two lncRNAs (RP11­60L3.1 and CTD­3195I5.3) and two microRNAs (has­miR­3913­1 and has­miR­891a) with highest accuracy prediction (AUC=0.79 in the training dataset and 0.64 in the test dataset) was selected. The signature had an ability to stratify patients into high­ and low­risk groups with significantly different survival rates (median 16.9 vs. 54.9 months, log­rank test P<0.001) in the training dataset, and its performance was validated for risk stratification in the test dataset (median 18.2 vs. 58.9 months, log­rank test P=0.002). Multivariable Cox regression analysis revealed that the signature was an independent prognostic factor for patients with bladder urothelial carcinoma (BLCA). A comparison of tumour node metastasis (TNM) stage and the signature indicated that the signature had better survival prediction power (AUCsignature=0.79/0.64 vs. AUCTNM=0.67/0.60, P<0.05). Functional analyses indicated that these prognostic genes from the signature may be involved in tumourigenesis­related biological processes and pathways. In conclusion, the multidimensional PCG­lncRNA­microRNA signature can be a novel prognostic marker to predict the survival of bladder cancer patients.


Asunto(s)
Carcinogénesis/genética , Pronóstico , Transcriptoma/genética , Neoplasias de la Vejiga Urinaria/genética , Anciano , Biomarcadores de Tumor/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , MicroARNs/genética , Persona de Mediana Edad , Estadificación de Neoplasias , Modelos de Riesgos Proporcionales , ARN Largo no Codificante/genética , Neoplasias de la Vejiga Urinaria/patología
12.
Genes (Basel) ; 7(10)2016 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-27775569

RESUMEN

The vast majority of lepidopterans, about 90%, are moths. Some moths, particularly their caterpillars, are major agricultural and forestry pests in many parts of the world. However, some other members of moths, such as the silkworm Bombyx mori, are famous for their economic value. Fire et al. in 1998 initially found that exogenous double-stranded RNA (dsRNA) can silence the homolog endogenous mRNA in organisms, which is called RNA interference (RNAi). Soon after, the RNAi technique proved to be very promising not only in gene function determination but also in pest control. However, later studies demonstrate that performing RNAi in moths is not as straightforward as shown in other insect taxa. Nevertheless, since 2007, especially after 2010, an increasing number of reports have been published that describe successful RNAi experiments in different moth species either on gene function analysis or on pest management exploration. So far, more than 100 peer-reviewed papers have reported successful RNAi experiments in moths, covering 10 families and 25 species. By using classic and novel dsRNA delivery methods, these studies effectively silence the expression of various target genes and determine their function in larval development, reproduction, immunology, resistance against chemicals, and other biological processes. In addition, a number of laboratory and field trials have demonstrated that RNAi is also a potential strategy for moth pest management. In this review, therefore, we summarize and discuss the mechanisms and applications of the RNAi technique in moths by focusing on recent progresses.

13.
Huan Jing Ke Xue ; 36(6): 2195-202, 2015 Jun.
Artículo en Zh | MEDLINE | ID: mdl-26387325

RESUMEN

Poly(AM-co-DVB) was synthesized by acrylamide(AM) and divinylbenzene(DVB) via the crosslinking reaction. The microscope structure and thermal stability of Poly(AM-co-DVB) were characterized by FT-IR, SEM and TG. Congo red (CR) was used to measure the adsorptive capacity of Poly (AM-co-DVB). The effects of initial pH, contact time and temperature on the adsorption of CR on Poly (AM-co-DVB) were investigated in this work. The kinetics, equilibrium, and thermodynamics of the adsorption process were also discussed. The results showed that the maximum adsorption capacities were 319.1 mg x g(-1) at pH = 7.25 and contact time = 3 h. The adsorption kinetics was well fitted by a pseudo-second-order model and the adsorption isotherms agreed well with the Langmuir model. The adsorption process was spontaneous process. Above all, the adsorption capacity of Poly (AM-co-DVB) on Congo red is significant.


Asunto(s)
Acrilamidas/química , Rojo Congo/aislamiento & purificación , Compuestos de Vinilo/química , Adsorción , Cinética , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Termodinámica
14.
Bioresour Technol ; 154: 313-21, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24412857

RESUMEN

This study aims to investigate the interaction and kinetic behavior of CO2 gasification of coal, biomass and their blends by thermogravimetry analysis (TG). The gas products evolved from gasification were measured online with Fourier Transform Infrared Spectroscopy (FTIR) coupled with TG. Firstly, TG experiments indicated that interaction between the coals and biomasses mainly occurred during co-gasification process. The most significant synergistic interaction occurred for LN with SD at the blending mass ratio 4:1. Furthermore, thermal kinetic analysis indicated that the activation energy involved in co-gasification decreased as the SD content increased until the blending ratio of SD with coal reached 4:1. The rise of the frequency factor indicated that the increase of SD content favored their synergistic interaction. Finally, FTIR analysis of co-gasification of SD with LN indicated that except for CO, most gases including CH3COOH, C6H5OH, H2O, etc., were detected at around 50-700°C.


Asunto(s)
Biomasa , Carbón Mineral , Gases/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Termogravimetría/métodos , Cinética , Oryza/química , Madera/química , Zea mays/química
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