1,081 research outputs found

    Effect of LeERF1 and LeERF2 overexpression in the response to salinity of young tomato (Solanumlycopersicum cv. Micro-Tom) seedlings

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    Ethylene responsive factors (ERFs) are important transcriptional regulators involved in plant responses to abiotic stress. LeERF1 and LeERF2, two members of the ERF family in tomato (Solanum lycopersicum), have previously been cloned. In this study, we investigated the salt-stress tolerance of transgenic tomato overexpressing LeERF1 and LeERF2. The transgenic lines had longer roots than wild-type (WT) plants under salt stress conditions. Furthermore, we examined physiological and biochemical indexes in the plants and found that overexpression of LeERF1 and LeERF2 enhanced the release of chlorophyll and free proline, but decreased the malondialdehyde contents of the plants. Transgenic tomato displayed higher superoxide dismutase and guaiacol peroxidase activity than WT tomato under high salinity conditions. Moreover, quantitative RT-PCR analysis revealed that the expression levels of salt stress-related genes, including TAS14, HVA22, LHA1, PR5, and RBOHC, which were upregulated in the transgenic plants. Therefore, overexpression of LeERF1 and LeERF2 positively modulates the ethylene-mediated response to salt stress in tomato

    Fe2O3 Nanoparticles Wrapped in Multi-walled Carbon Nanotubes With Enhanced Lithium Storage Capability

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    We have designed a novel hybrid nanostructure by coating Fe2O3 nanoparticles with multi-walled carbon nanotubes to enhance the lithium storage capability of Fe2O3. The strategy to prepare Fe2O3@MWCNTs involves the synthesis of Fe nanoparticles wrapped in MWCNTs, followed by the oxidation of Fe nanoparticles under carbon dioxide. When used as the anode in a Li-ion battery, this hybrid material (70.32 wt% carbon nanotubes, 29.68 wt% Fe2O3) showed a reversible discharge capacity of 515ā€…mAhgāˆ’1 after 50 cycles at a density of 100ā€…mAgāˆ’1 and the capacity based on Fe2O3 nanoparticles was calculated as 1147ā€…mAhgāˆ’1, Three factors are responsibile for the superior performance: (1) The hollow interiors of MWCNTs provide enough spaces for the accommodation of large volume expansion of inner Fe2O3 nanoparticles, which can improving the stability of electrode; (2) The MWCNTs increase the overall conductivity of the anode; (3) A stable solid electrolyte interface film formed on the surface of MWCNTs may reduce capacity fading

    Experimental study on flow-induced motion and energy conversion for two triangular prisms in tandem arrangement

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    Experimental tests on two tandem triangular prisms were accomplished in synergistic flow-induced motion (FIM) to collect ocean current energy (OCE) with varied spacing ratios and Reynolds number ranges. Typical FIM responses and energy conversion are discussed and presented. The effects of parameters (system stiffness, spacing ratio, and load resistance) were considered to improve the energy harvesting of the system. The main findings can be summarized as follows: 1) with varied spacing ratios between the two tandem prisms, the active power (Pharn) was up to 1.95 times that of the single triangular prism (STP); 2) In general, the harnessed OCE capacity of the upstream triangular prism (UTP) was improved, while the energy harvesting of the downstream triangular prism (DTP) was suppressed by the interaction of the two prisms, 3) In the tests, electricity was generated at U = 0.516Ā m/s, and the active power, which consistently increased as flow velocity increased, reached Pharn = 32.24Ā W, with a corresponding efficiency of Ī·harn = 10.31%; and 4) The best energy conservation performance for harvesting the OCE occurred at L/D = 5, and the optimal load resistance was found at RL = 11 Ī©

    Granulocyte colony-stimulating factor increases the therapeutic efficacy of bone marrow mononuclear cell transplantation in cerebral ischemia in mice

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    <p>Abstract</p> <p>Background</p> <p>Bone marrow mononuclear cell (BMMC) transplantation is a promising therapy for cerebral ischemia; however, little is known if its therapeutic efficacy may be improved by co-administration of potential modulatory factors in vivo. To explore this possibility, the present study examined the effect of BMMCs and G-CSF on cell proliferation, early neuronal development and neurological function recovery in experimental cerebral ischemia relative to controls that received neither treatment.</p> <p>Result</p> <p>Ischemia/infarct area was significantly reduced in BMMCs+G-CSF group relative to animal groups treated with BMMCs only, G-CSF only or saline. Transplanted BMMCs were found to colocalize with the proliferative cell nuclear antigen (PCNA) and the immature neuronal marker doublecortin (DCX). The BMMCs+G-CSF group showed increased numerical density of cells expressing PCNA and DCX, improved performance in adhesive sticker removal test and reduced neurological function severity scores relative to other groups in a time-dependent manner.</p> <p>Conclusion</p> <p>BMMCs and G-CSF co-administration exhibits synergistic beneficial effect over time. This effect could be at least partially related to increased proliferation and differentiation of bone marrow stem cells and enhanced host brain regeneration and functional recovery. The results suggest that G-CSF can increase the therapeutic efficacy of BMMCs transplantation in an experimental mouse model of cerebral ischemia.</p

    Using microneedle array electrodes for non-invasive electrophysiological signal acquisition and sensory feedback evoking

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    Introduction: Bidirectional transmission of information is needed to realize a closed-loop human-machine interaction (HMI), where electrophysiological signals are recorded for man-machine control and electrical stimulations are used for machine-man feedback. As a neural interface (NI) connecting man and machine, electrodes play an important role in HMI and their characteristics are critical for information transmission.Methods: In this work, we fabricated a kind of microneedle array electrodes (MAEs) by using a magnetization-induced self-assembly method, where microneedles with a length of 500ā€“600Ā Ī¼m and a tip diameter of āˆ¼20Ā Ī¼m were constructed on flexible substrates. Part of the needle length could penetrate through the subjectsā€™ stratum corneum and reach the epidermis, but not touch the dermis, establishing a safe and direct communication pathway between external electrical circuit and internal peripheral nervous system.Results: The MAEs showed significantly lower and more stable electrode-skin interface impedance than the metal-based flat array electrodes (FAEs) in various testing scenarios, demonstrating their promising impedance characteristics. With the stable microneedle structure, MAEs exhibited an average SNR of EMG that is more than 30% higher than FAEs, and a motion-intention classification accuracy that is 10% higher than FAEs. The successful sensation evoking demonstrated the feasibility of the MAE-based electrical stimulation for sensory feedback, where a variety of natural and intuitive feelings were generated in the subjects and thereafter objectively verified through EEG analysis.Discussion: This work confirms the application potential of MAEs working as an effective NI, in both electrophysiological recording and electrical stimulation, which may provide a technique support for the development of HMI

    Distribution, characterization, and induction of CD8+ regulatory T cells and IL-17-producing CD8+ T cells in nasopharyngeal carcinoma

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    <p>Abstract</p> <p>Background</p> <p>CD8<sup>+ </sup>effector cells often have an antitumor function in patients with cancer. However, CD8<sup>+</sup>Foxp3<sup>+ </sup>regulatory T cells (Tcregs) and interleukin (IL)-17-producing CD8<sup>+ </sup>T cells (Tc17 cells) also derive from the CD8<sup>+ </sup>T cell lineage. Their role in the antitumor response remains largely unknown. In the present study, we aimed to investigate the distribution, characterization, and generation of CD8<sup>+ </sup>Tcregs and Tc17 cells in NPC patients.</p> <p>Methods</p> <p>Peripheral blood and tumor biopsy tissues from 21 newly diagnosed patients with nasopharyngeal carcinoma (NPC) were collected, along with peripheral blood from 21 healthy donors. The biological characteristics of Tcregs and Tc17 cells from blood and tumor tissues were examined by intracellular staining, tetramer staining and fluorescence-activated cell sorting (FACS) analysis. The suppressive function of Tcregs was investigated using a proliferation assay that involved co-culture of sorted CD8<sup>+</sup>CD25<sup>+ </sup>T cells with naĆÆve CD4<sup>+ </sup>T cells <it>in vitro</it>.</p> <p>Results</p> <p>We observed an increased prevalence of Tcregs and Tc17 cells among tumor-infiltrating lymphocytes (TILs) and different distribution among peripheral blood mononuclear cells (PBMCs) in NPC patients. Cytokine profiles showed that the Tcregs expressed a high level of IL-10 and low level of transforming growth factor Ī², whereas Tc17 cells expressed a high level of tumor necrosis factor Ī±. Interestingly, both subsets expressed a high level of interferon Ī³ in TILs, and the Tcregs suppressed naĆÆve CD4<sup>+ </sup>T cell proliferation by a cell contact-dependent mechanism <it>in vitro</it>. Moreover, we demonstrated the existence of Epstein-Barr virus latent membrane protein (LMP) 1 and LMP2 antigen-specific Tcregs in NPC.</p> <p>Conclusions</p> <p>Our data provide new insights into the composition and function of CD8<sup>+ </sup>T-cell subsets in NPC, which may have an important influence on NPC immunotherapy.</p
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