284 research outputs found

    Le regole del gioco: Primo incontro con l'ingegneria strategica

    Get PDF
    Cu particles decorated carbon composite microspheres (CCMs) with a unique sesame ball structure have been prepared by combining the mass-producible spray drying technique with calcinations. The conventional cuprammonium cellulose complex solution obtained by dissolving cellulose in a cuprammonia solution has been applied as raw materials for the preparation of Cu­(NH<sub>3</sub>)<sub>4</sub><sup>2+</sup>/cellulose complex microspheres via a spray drying process. The resulted Cu­(NH<sub>3</sub>)<sub>4</sub><sup>2+</sup>/cellulose complex microspheres are then transformed into the Cu particles homogeneously decorated porous carbon spheres <i>in situ</i> by calcinations at 450 or 550 °C. The coordination effect between the Cu­(NH<sub>3</sub>)<sub>4</sub><sup>2+</sup> species and the hydroxyl groups of the cellulose macromolecules has been exploited for directing the dispersion of the Cu particles in the resultant composite CCMs. The antimicrobial effects of the CCMs are evaluated by determining the minimum growth inhibitory concentrations using Staphylococcus aureus and Escherichia coli as representatives, respectively. The CCMs show high efficiency catalytic properties to the conversion of 4-nitrophenol to 4-aminophenol using NaBH<sub>4</sub> as a reductant in a mild condition. The recyclability and stability of the CCM catalysts have also been studied

    Comprehensive analysis of mitogen-activated protein kinase cascades in chrysanthemum

    Get PDF
    Background Mitogen-activated protein kinase (MAPK) cascades, an important type of pathway in eukaryotic signaling networks, play a key role in plant defense responses, growth and development. Methods Phylogenetic analysis and conserved motif analysis of the MKK and MPK families in Arabidopsis thaliana, Helianthus annuus and Chrysanthemum morifolium classified MKK genes and MPK genes. qRT-PCR was used for the expression patterns of CmMPK and CmMKK genes, and yeast two-hybrid assay was applied to clear the interaction between CmMPKs and CmMKKs. Results We characterized six MKK genes and 11 MPK genes in chrysanthemum based on transcriptomic sequences and classified these genes into four groups. qRT-PCR analysis demonstrated that CmMKKs and CmMPKs exhibited various expression patterns in different organs of chrysanthemum and in response to abiotic stresses and phytohormone treatments. Furthermore, a yeast two-hybrid assay was applied to analyze the interaction between CmMKKs and CmMPKs and reveal the MAPK cascades in chrysanthemum. Discussion Our data led us to propose that CmMKK4-CmMPK13 and CmMKK2-CmMPK4 may be involved in regulating salt resistance and in the relationship between CmMKK9 and CmMPK6 and temperature stress

    Macrophage Foam Cell-Targeting Immunization Attenuates Atherosclerosis

    Get PDF
    Background: Macrophage foam cells (FCs) play a crucial role in the initiation and progression of atherosclerosis. Reducing the formation or inducing the removal of FCs could ameliorate atherosclerosis. The present study examined whether the whole-cell vaccination using FCs could be used as novel prevention and treatment strategies to battle atherosclerosis.Methods: ApoE−/− mice with initial or established atherosclerosis were subcutaneously immunized three times with FCs in Freund's adjuvant.Results: Immunization with FCs resulted in an overt reduction of atherosclerotic lesion in the whole aorta and the aortic root with enhanced lesion stability. Subsequent study in mechanism showed that FCs vaccination dramatically increased CD4+ T cell and CD8+ T cell populations. Immunization with FCs significantly raised the plasma FCs-specific IgG antibodies. Of note, the FCs immune plasma could selectively recognize and bind to FC. FCs immune plasma significantly blocked the process of FCs formation, finally reduced the accumulation of FCs in plaque. Additionally, it was observed that FCs immunization down-regulated the expression level of atherosclerosis related pro-inflammatory cytokines, including IFN-Îł, MCP-1, and IL-6 and enhanced the lesion stability with a significant increase in TGF-ÎČ1 level and collagen content.Conclusions: These findings demonstrate that the whole-cell vaccination using FCs significantly decreased lesion development and positively modulated lesion progression and stability by targeting FCs. The whole-cell FCs vaccine might represent a potential novel strategy for development of new antibodies and vaccines to the prevention or treatment of atherosclerosis

    Phosphorous fertilization alleviates drought effects on Alnus cremastogyne by regulating its antioxidant and osmotic potential

    Get PDF
    Alnus cremastogyne, a broad-leaved tree endemic to south-western China, has both commercial and restoration importance. However, little is known of its morphological, physiological and biochemical responses to drought and phosphorous (P) application. A randomized experimental design was used to investigate how drought affected A. cremastogyne seedlings, and the role that P applications play in these responses. Drought had significant negative effects on A. cremastogyne growth and metabolism, as revealed by reduced biomass (leaf, shoot and root), leaf area, stem diameter, plant height, photosynthetic rate, leaf relative water content, and photosynthetic pigments, and a weakened antioxidative defence mechanism and high lipid peroxidation level. However, the reduced leaf area and enhanced osmolyte (proline and soluble sugars) accumulation suggests drought avoidance and tolerance strategies in this tree. Applying P significantly improved the leaf relative water content and photosynthetic rate of drought-stressed seedlings, which may reflect increased anti-oxidative enzyme (superoxide dismutase, catalase and peroxidase) activities, osmolyte accumulation, soluble proteins, and decreased lipid peroxidation levels. However, P had only a slight or negligible effect on the well-watered plants. A. cremastogyne is sensitive to drought stress, but P facilitates and improves its metabolism primarily via biochemical and physiological rather than morphological adjustments, regardless of water availability.Instituto de FisiologĂ­a Vegeta

    Spray drying assisted assembly of ZnO nanocrystals using cellulose as sacrificial template and studies on their photoluminescent and photocatalytic properties

    Get PDF
    The conventional zincoxen cellulose solution, which was obtained by dissolving cellulose with the zincoxen solvent (tri(ethylenediamine) zinc hydroxide solution, Zn(EDA)), has been used as raw materials for the preparation of zincoxen/cellulose complex microspheres via a spray drying technique. The obtained zincoxen/cellulose microspheres are turned into assemblies (or clusters) of ZnO nanocrystals by calcining the complex microspheres at 500 or 700\ua0°C. For the preparation, zincoxen plays both the role as solvent for cellulose and precursor for the ZnO nanocrystals. While, the cellulose acts as assembly agent during the spray drying step and sacrificial templates in the calcinations process. The content of cellulose in the zincoxen cellulose aqueous solution and the calcination temperature show significant impacts on the morphology, porosity, optical properties and photocatalytic activity of the resulted ZnO nanocrystal assemblies. The structures, morphology and porosity have been investigated based on XRD, SEM, TEM and N adsorption-desorption technique. The lattice parameters have been fitted by the Rietveld refinement and the strains in the crystals have been studied. Under ultraviolet light irradiation, all the assemblies of ZnO nanocrystals exhibit high photocatalytic activity for methyl orange degradation in aqueous solution and also satisfied reusability and stability of morphology and composition

    Overexpression of Phosphate Transporter Gene CmPht1;2 Facilitated Pi Uptake and Alternated the Metabolic Profiles of Chrysanthemum Under Phosphate Deficiency

    Get PDF
    Low availability of phosphorus (P) in the soil is the principal limiting factor for the growth of cut chrysanthemum. Plant phosphate transporters (PTs) facilitate acquisition of inorganic phosphate (Pi) and its homeostasis within the plant. In the present study, CmPht1;2 of the Pht1 family was cloned from chrysanthemum. CmPht1;2 is composed of 12 transmembrane domains and localized to the plasma membrane. Expression of CmPht1;2 in roots was induced by Pi starvation. Chrysanthemum plants with overexpression of CmPht1;2 (Oe) showed higher Pi uptake, as compared to the wild type (WT), both under Pi-starvation and Pi-sufficient conditions, and also showed a higher root biomass compared to WT in the Pi-starvation conditions. Seven days after the P-deficiency treatment, 85 distinct analytes were identified in the roots and 27 in the shoots between the Oe1 plant and WT, in which sophorose, sorbitol (sugars), hydroxybutyric acid (organic acids), and ornithine (amino acid) of CmPht1;2 overexpressing chrysanthemum are specific responses to P-starvation

    Integrating Strategies of Herbal Metabolomics, Network Pharmacology, and Experiment Validation to Investigate Frankincense Processing Effects

    Get PDF
    In-depth research on processing can promote the globalization of processed herbs. The purpose of this study is to propose an improved strategy for processing effect investigation. Frankincense and processed frankincense were used as research subjects. First, high-speed countercurrent chromatography (HSCCC) and preparation high-performance liquid chromatography (PHPLC) techniques were used for major compounds isolation and minor compounds concentration. Processed frankincense was subjected to two stepwise solvent systems, namely, n-hexane:ethanol:water (6:5:1) and n-hexane:methyl-acetate:acetonitrile:water (4:4:3:4), to yield 12 fractions, and 18 compounds were further separated. Second, a comprehensive metabolomic analysis conducted by ultrahigh-performance liquid-chromatography/electrospray-ionization mass spectrometry (UHPLC-Qtof-MS) coupled with multivariate statistics was performed to fully characterize the chemical components and discover the potential biomarkers between frankincense and processed frankincense. In total, 81 metabolites, including the 18 separated compounds, were selected as potential biomarkers between frankincense and processed frankincense among 153 detected compounds for their VIP values of greater than one. The tirucallane-type compounds and components with 9,11-dehydro structures clearly occurred at high levels in the processed frankincense, while lupine-type compounds and those with 11-keto structures were significantly higher in frankincense. Then, a network pharmacology model was constructed to decipher the potential mechanisms of processing. Intestinal absorption properties prediction indicated the possibility of processing-related absorption enhancement. A systematic analysis of the constructed networks showed that the C-T network was constructed with 18 potential biomarkers and 69 targets. TNF and IL-1ÎČ were among the top-ranked and were linked by 8 and 7 pathways, which were mainly involved in inflammation. The arachidonic acid metabolism pathway exhibited the highest number of target connections. Finally, the prediction was validated experimentally by an intestinal permeability and efficacy assay. The experiments provided convincing evidence that processed frankincense harbored stronger inhibition effects toward TNF-α-, IL-1ÎČ- and arachidonic acid-induced platelet aggregation. The processing procedure leads to changes of the chemical metabolites, which triggers the enhancement of absorption and cure efficiency. The global change of the metabolites, absorption and pharmacological effects of processing were depicted in a systematic manner

    Synthesis and characterization of magnetically separable Ag nanoparticles decorated mesoporous Fe3O4@carbon with antibacterial and catalytic properties

    Get PDF
    Mesoporous composite particles of carbon inlaid with FeO nanoparticles (designated as FeO@carbon) with a novel bowl structure and magnetic separation property were fabricated by a spray drying assisted template method using chitosan as carbon precursor and silica nanoparticles as pore directing agent. The influence of the contents among FeO nanoparticles, chitosan and silica nanoparticle on the formation of porous FeO@carbon composite particles has been discussed. Ag nanoparticles were then deposited onto the surface of mesoporous FeO@carbon substrates using silver acetate as precursor with the assistance of ultrasound treatment. The matrices of Ag nanoparticles decorated FeO@carbon composite particles (denoted as Ag-(FeO@carbon)) were derived and characterized with scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier-transform infrared (FT-IR) spectroscopy, nitrogen adsorption-desorption, and magnetic property measurements. The Ag-(FeO@carbon) composites showed efficient antibacterial activities to Escherichia coli and Staphylococcus aureus, high catalytic activity to the reduction of 4-nitrophenol (4-NP) in the presence of NaBH, strong adsorption ability to organic molecules, and efficient separability under a magnetic field

    The Abundance and Diversity of Soil Fungi in Continuously Monocropped Chrysanthemum

    Get PDF
    Chrysanthemum is an important ornamental plant which is increasingly being monocropped. Monocropping is known to affect both fungal abundance and species diversity. Here, quantitative PCR allied with DGGE analysis was used to show that fungi were more abundant in the rhizosphere than in the bulk soil and that the fungal populations changed during the growth cycle of the chrysanthemum. The majority of amplified fragments appeared to derive from Fusarium species, and F. oxysporum and F. solani proved to be the major pathogenic species which are built up by monocropping

    Phosphorous application improves drought tolerance of phoebe zhennan

    Get PDF
    Phoebe zhennan (Gold Phoebe) is a threatened tree species in China and a valuable and important source of wood and bioactive compounds used in medicine. Apart from anthropogenic disturbances, several biotic constraints currently restrict its growth and development. However, little attention has been given to building adaptive strategies for its conservation by examining its morphological and physio-biochemical responses to drought stress, and the role of fertilizers on these responses. A randomized experimental design was used to investigate the effects of two levels of irrigation (well-watered and drought-stressed) and phosphorous (P) fertilization treatment (with and without P) to assess the morphological and physio-biochemical responses of P. zhennan seedlings to drought stress. In addition, we evaluated whether P application could mitigate the negative impacts of drought on plant growth and metabolism. Drought stress had a significant negative effect on the growth and metabolic processes of P. zhennan. Despite this, reduced leaf area, limited stomatal conductance, reduced transpiration rate, increased water use efficiency, enhanced antioxidant enzymes activities, and osmolytes accumulation suggested that the species has good adaptive strategies for tolerating drought stress. Application of P had a significant positive effect on root biomass, signifying its improved water extracting capacity from the soil. Moreover, P fertilization significantly increased leaf relative water content, net photosynthetic rate, and maximal quantum efficiency of PSII under drought stress conditions. This may be attributable to several factors, such as enhanced root biomass, decreased malondialdehyde content, and the up-regulation of chloroplast pigments, osmolytes, and nitrogenous compounds. However, P application had only a slight or negligible effect on the growth and metabolism of well-watered plants. In conclusion, P. zhennan has a strong capability for drought resistance, while P application facilitates and improves drought tolerance mostly through physio-biochemical adjustments, regardless of water availability. It is imperative to explore the underlying metabolic mechanisms and effects of different levels of P fertilization on P. zhennan under drought conditions in order to design appropriate conservation and management strategies for this species, which is at risk of extinction.Fil: Tariq, Akash. Chinese Academy of Sciences; RepĂșblica de ChinaFil: Pan, Kaiwen. Chinese Academy of Sciences; RepĂșblica de ChinaFil: Olatunji, Olusanya A.. Chinese Academy of Sciences; RepĂșblica de ChinaFil: Graciano, Corina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - La Plata. Instituto de FisiologĂ­a Vegetal. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de FisiologĂ­a Vegetal; ArgentinaFil: Li, Zilong. Chinese Academy of Sciences; RepĂșblica de ChinaFil: Sun, Feng. Chinese Academy of Sciences; RepĂșblica de ChinaFil: Sun, Xiaoming. Chinese Academy of Sciences; RepĂșblica de ChinaFil: Song, Dagang. Chinese Academy of Sciences; RepĂșblica de ChinaFil: Chen, Wenkai. Chinese Academy of Sciences; RepĂșblica de ChinaFil: Zhang, Aiping. Chinese Academy of Sciences; RepĂșblica de ChinaFil: Wu, Xiaogang. Chinese Academy of Sciences; RepĂșblica de ChinaFil: Zhang, Lin. Chinese Academy of Sciences; RepĂșblica de ChinaFil: Mingrui, Deng. Chinese Academy of Sciences; RepĂșblica de ChinaFil: Xiong, Qinli. Chinese Academy of Sciences; RepĂșblica de ChinaFil: Liu, Chenggang. Chinese Academy of Sciences; RepĂșblica de Chin
    • 

    corecore