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Mycopathologia - Fungi of the genus Fusarium are well known as major plant pathogens but also cause a broad spectrum of human infections. Sixty-three clinical isolates, collected during...  相似文献   
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Supplying a sufficient amount of available iron (Fe) for plant growth in hydroponic nutrient solutions is a great challenge. The chelators commonly used to supply Fe in nutrient solutions have several disadvantages and may negatively affect plant growth. In this research study we have synthesized certain Fe-amino acid chelates, including Fe-arginine [Fe(Arg)2], Fe-glycine [Fe(Gly)2], and Fe-histidine [Fe(His)2], and evaluated their efficacy as an Fe source for two tomato cultivars (Lycopersicon esculentum Mill. cvs. ‘Rani’ and ‘Sarika’) grown in nutrient solution. Application of Fe-amino acid chelates significantly increased root and shoot dry matter yield of both tomato cultivars compared with Fe-EDTA. Tomato plants supplied with Fe-amino acid chelates also accumulated significantly higher levels of Fe, Zn, and N in their roots and shoots compared with those supplied with Fe-EDTA. In ‘Sarika’, the effect of Fe-amino acid chelates on shoot Fe content was in the order Fe(His)2?>?Fe(Gly)2?>?Fe(Arg)2. In ‘Rani’, the addition of all synthesized Fe-amino acid chelates significantly increased activity of ascorbate peroxidase (APX) in comparison with Fe-EDTA, whereas in ‘Sarika’, only Fe(His)2 increased shoot APX activity. The results obtained indicated that using Fe-amino acid chelates in the nutrient solution could supply a sufficient amount of Fe for plant uptake and also improve root and shoot growth of tomato plants, although this increase was cultivar-dependent. According to the results, Fe-amino acid chelates can be used as an alternative for Fe-EDTA to supply Fe in nutrient solutions.  相似文献   
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Molecular Biology Reports - Monoclonal antibodies (mAbs) are widely employed as invaluable therapeutics for a vast number of human disorders. Several approaches have been introduced for the...  相似文献   
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Here, we describe the fabrication of an electrochemical immunoglobulin E (IgE) aptasensor using enzyme-linked aptamer in the sandwich assay method and thionine as redox probe. In this protocol, 5′-amine-terminated IgE aptamer and thionine were covalently attached on glassy carbon electrode modified with carbon nanotubes/ionic liquid/chitosan nanocomposite. Furthermore, another IgE aptamer was modified with biotin and enzyme horseradish peroxidase (HRP), which attached to the aptamer via biotin–streptavidin interaction. Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry were performed at each stage of the chemical modification process to confirm the resulting surface changes. The presence of IgE induces the formation of a double aptamer sandwich structure on the electrode, and the electrocatalytic reduction current of thionine in the presence of hydrogen peroxide was measured as the sensor response. Under optimized conditions and using differential pulse voltammetry as the measuring technique, the proposed aptasensor showed a low detection limit (6 pM) and high sensitivity (1.88 μA nM−1). This aptasensor also exhibited good stability and high selectivity for IgE detection without an interfering effect of some other proteins such as bovine serum albumin (BSA) and lysozyme. The application of the aptasensor for IgE detection in human serum sample was also investigated. The proposed protocol is quite promising as an alternative sandwich approach for various protein assays.  相似文献   
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Tyrosinase is a type 3 copper enzyme responsible for skin pigmentation disorders, skin cancer, and enzymatic browning of vegetables and fruits. In the present article, 12 small molecules of 2‐benzylidenehydrazine‐1‐carbothioamide were designed, synthesized and evaluated for their anti‐tyrosinase activities followed by molecular docking and pharmacophore‐based screening. Among synthesized thiosemicarbazone derivatives, one compound, (2E)‐2‐[(4‐nitrophenyl)methylidene]hydrazine‐1‐carbothioamide, is the strongest inhibitor of mushroom tyrosinase with IC50 of 0.05 μM which demonstrated a 128‐fold increase in potency compared to the positive control. Kinetic studies also revealed mix type inhibition by this compound. Docking studies confirmed the complete fitting of the synthesized compounds into the tyrosinase active site. The results underline the potential of 2‐benzylidenehydrazine‐1‐carbothioamides as potent pharmacophore to extend the tyrosinase inhibition in drug discovery.  相似文献   
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The activity of a lipase from a newly isolated Pseudomonas sp. was investigated in the presence of organic solvents and imidazolium chloride‐based ionic liquids (IL) such as BMIM[Cl] and HMIM[Cl]. The lipase activity in the presence of IL was higher compared to that in common organic solvents such as methanol and 2‐propanol. A possible explanation for the enzyme activation might be the structural changes induced in the protein in organic systems. Since IL quench the intensity of fluorescence emission, it was not possible to investigate the major factor that influences the enzyme behavior in these new organic salts. Furthermore, the enzyme exhibited excellent activity in buffer mixtures containing both organic solvent and IL. The stability of the lipase at 50°C was considerably increased in the presence of 20% BMIM[Cl] compared with the untreated lipase in aqueous medium. The light scattering method clearly showed that prevention of aggregation could be the reason for thermal stabilization at 50°C in reactions containing IL. Kinetic analysis of the enzyme in the presence of different concentrations of IL showed that the Km value increased from 0.45 mM in aqueous buffer to 2.4 mM in 50% v/v BMIM[Cl]/buffer. The increase in Km indicates that IL can significantly reduce the binding affinity of the substrate to the enzyme. Also, a linear correlation was observed between the BMIM[Cl] concentration and Vmax of the enzyme. As the concentration of BMIM[Cl] increased from 10 to 50% v/v, the Vmax value increased from 1.8 to 46 μM/min.  相似文献   
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Combination therapies, using medicinal herbs, are broadly recommended to attenuate the chemotherapy adverse effects. Based on our previous findings considering the anti-leukaemic effects of ginger extract on acute lymphoblastic leukaemia (ALL) cells, the present study was aimed to investigate the anti-cancer role of this pharmaceutical plant on ALL mice models. Moreover, we worked towards identifying the most anti-leukaemic derivative of ginger and the mechanism through which it may exert its cytotoxic impact. In vivo experiments were performed using five groups of six C57BL/6 nude mice, and the anti-leukaemic activity of ginger extract alone or in combination with methotrexate (MTX) was examined. Results showed increased survival rate and reduced damages in mice brain and liver tissues. Subsequently, MTT assay demonstrated synergistic growth inhibitory effect of 6-shogaol (6Sh) and MTX on ALL cell lines and patients primary cells. Eventually, the molecular anti-neoplastic mechanism of 6Sh was evaluated using Bioinformatics. Flow cytometry illustrated 6Sh-mediated apoptosis in Nalm-6 cells confirmed by Western blotting and RT-PCR assays. Further analyses exhibited the generation of reactive oxygen species (ROS) through 6Sh. The current study revealed the in vivo novel anti-leukaemic role of ginger extract, promoted by MTX. Moreover, 6-shogaol was introduced as the major player of ginger cytotoxicity through inducing p53 activity and ROS generation.  相似文献   
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Stem cells from human exfoliated deciduous teeth (SHED) are highly proliferative, clonogenic and multipotent stem cells with a neural crest cell origin. Additionally, they can be collected with minimal invasiveness in comparison with other sources of mesenchymal stem cells (MSCs). Therefore, SHED could be a desirable option for potential therapeutic applications. In this study, SHEDs were established from enzyme-disaggregated deciduous dental pulp obtained from 6 to 9 year-old children. The cells had typical fibroblastoid morphology and expressed antigens characteristic of MSCs, STRO1, CD146, CD45, CD90, CD106 and CD166, but not the hematopoietic and endothelial markers, CD34 and CD31, as assessed by FACS analysis. Differentiation assessment revealed a strong osteogenic and adipogenic potential of SHEDs. In order to further evaluate the in vitro differentiation potential of SHED into neural cells, a simple short time growth factor-mediated induction was used. Immunofluorescence staining and flow cytometric analysis revealed that SHED rapidly expressed nestin and b-III tubulin, and later expressed intermediate neural markers. In addition, the intensity and percentages of nestin and b-III tubulin and mature neural markers (PSA-NCAM, NeuN, Tau, TH, or GFAP) increased significantly following treatment. Moreover, RT-PCR and Western blot analyses showed that the neural markers were strongly up-regulated after induction. In conclusion, these results provide evidence that SHED can differentiate into neural cells by the expression of a comprehensive set of genes and proteins that define neural-like cells in vitro. SHED cells might be considered as new candidates for the autologous transplantation of a wide variety of neurological diseases and neurotraumatic injuries.  相似文献   
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