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1.
Plant Physiol ; 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33905518

RESUMO

Plant responses to pathogen attacks and to high temperature stress (HTS) are distinct in nature but generally share several signaling components. How plants produce specific responses through these common signaling intermediates remains elusive. With the help of reverse-genetics approaches, we describe here the mechanism underlying trade-offs in pepper (Capsicum annuum) between growth, immunity and thermotolerance. The NAC-type transcription factor CaNAC2c was induced by HTS and Ralstonia solanacearum infection (RSI). CaNAC2c inhibited pepper growth, promoted immunity against RSI by activating jasmonate-mediated immunity and H2O2 accumulation, and promoted HTS responses by activating Heat shock factor A5 (CaHSFA5) transcription and blocking H2O2 accumulation. We show that CaNAC2c physically interacts with CaHSP70 and CaNAC029 in a context-specific manner. Upon HTS, CaNAC2c-CaHSP70 interaction in the nucleus protected CaNAC2c from degradation and resulted in the activation of thermotolerance by increasing CaNAC2c binding and transcriptional activation of its target promoters. CaNAC2c did not induce immunity-related genes under HTS, likely due to the degradation of CaNAC029 by the 26S proteasome. Upon RSI, CaNAC2c interacted with CaNAC029 in the nucleus and activated jasmonate-mediated immunity but was prevented from activating thermotolerance-related genes. In non-stressed plants, CaNAC2c was tethered outside the nucleus by interaction with CaHSP70, and thus was unable to activate either immunity or thermotolerance. Our results indicate that pepper growth, immunity and thermotolerance are coordinately and tightly regulated by CaNAC2c via its inducible expression and differential interaction with CaHSP70 and CaNAC029.

2.
Adv Mater ; : e2100745, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33876867

RESUMO

High-entropy materials are new-generation electrocatalysts for water splitting due to their excellent reactivity and highly tailorable electrochemical properties. Herein, a powerful top-level design strategy is reported to guide and design advanced high-entropy electrocatalysts by establishing reaction models (e.g., reaction energy barrier, conductivity, adsorption geometries for intermediates, and rate-determining step) to predict performance with the help of density functional theory (DFT) calculations. Accordingly, novel high-entropy Co-Cu-Fe-Mo (oxy)hydroxide electrocatalysts are fabricated by a new low-temperature electrochemical reconstruction method and their oxygen evolution reaction (OER) properties are thoroughly characterized. These as-prepared quaternary metallic (oxy)hydroxides present much better OER performance than ternary Co-Cu-Mo (oxy)hydroxide, Co-Fe-Mo (oxy)hydroxide, and other counterparts, and are demonstrated with a low overpotential of 199 mV at a current density of 10 mA cm-2 and a 48.8 mV dec-1 Tafel slope in 1 m KOH and excellent stability without decay over 72 h. The performance enhancement mechanism is also unraveled by synchrotron radiation. The work verifies the usefulness of high-entropy design and the great synergistic effect on OER performance by the incorporation of four elements, and also provides a new method for the construction of advanced high-entropy materials for energy conversion and storage.

3.
Opt Lett ; 46(9): 2208-2211, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33929455

RESUMO

Computed tomography imaging spectrometry (CTIS) is a snapshot hyperspectral imaging technique that can obtain a three-dimensional (${2D +}\lambda$) data cube of the target scene within a single exposure. Previous studies of CTIS suggest that reconstructions usually suffer from severe artifacts due to the limited number of projections available. To overcome this limitation, an iterative algorithm combining superiorization and guided image filtering is proposed to explore the intrinsic properties of the hyperspectral data cube as well as the characteristics of zero-order diffraction for the first time, to the best of our knowledge. Results from both simulative studies and proof-of-concept experiments demonstrate its superiority in suppressing artifacts and improving precision over the frequently used expectation maximization algorithm.

4.
Front Immunol ; 12: 631249, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33708221

RESUMO

The most commonly used strains in experimental research, including genetically modified strains, are C57BL/6 mice. However, so far, no reliable model for rheumatoid arthritis is available, mainly due to the restriction by the MHC class II haplotype H-2b. Collagen-induced arthritis (CIA) is the most widely used animal model of rheumatoid arthritis, but C57BL/6 strain is resistant to CIA because there is no collagen II peptide associated with H-2b. To establish a rheumatoid arthritis model in C57BL/6 mice, we immunized C57BL/6NJ (B6N) mice with human cartilage oligomeric matrix protein (COMP), which induced severe arthritis with high incidence, accompanied by a strong auto-antibody response. Native COMP was required, as denatured COMP lost its ability to induce arthritis in B6N mice. An immunodominant COMP peptide was identified as the key T cell epitope, with a perfect fit into the Ab class II peptide binding pocket. A critical amino acid in this peptide was found to be phenylalanine at position 95. Recombinant COMP mutated at position 95 (COMP_F95S) lost its ability to induce arthritis or a strong immune response in the B6N mice. In conclusion, A new model for RA has been established using C57BL/6 mice through immunization with COMP, which is dependent on a COMP specific peptide binding Ab, thus in similarity with CIA in Aq expressing strains.

5.
Audiol Neurootol ; : 1-11, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33540407

RESUMO

INTRODUCTION: The role of social support in the relief of tinnitus distress and related mechanisms remains unclear. This study aimed to confirm a hypothesis that the influence of social support on tinnitus distress is mediated by resilience and self-esteem. METHODS: The Social Support Rating Scale, Connor-Davidson Resilience Scale, Positive Version of Rosenberg Self-Esteem Scale, and Tinnitus Handicap Inventory were used to assess 296 patients who experience chronic subjective tinnitus. The collected data were subjected to correlational analysis, mediating effect testing, and structural equation model analysis using R 3.3.1 with the mediate and lavaan packages. RESULTS: The result showed that social support had significant positive correlations with resilience and self-esteem, while resilience and self-esteem had significant negative correlations with tinnitus distress. Furthermore, social support indirectly affected tinnitus distress through the full mediating effects of resilience and self-esteem and could indirectly affect resilience through the partial mediating effects of self-esteem. CONCLUSION: These results suggested that the key to social support for alleviating tinnitus distress lies in the development of patients' resilience and self-esteem. Promoting the development of positive psychological quality of tinnitus patients and improving their perception of social support may become the new approaches of clinical management of tinnitus.

6.
Artigo em Inglês | MEDLINE | ID: mdl-33555219

RESUMO

WRKY transcription factors have been implicated in plant response to pathogens, but how WRKY-mediated networks are organized and operate to produce appropriate transcriptional outputs remains largely unclear. Here, we identify a member of the WRKY family from pepper (Capsicum annuum), CaWRKY28, that physically interacts with CaWRKY40, a positive regulator of pepper immunity and thermotolerance. We confirmed CaWRKY28/CaWRKY40 interaction by co-immunoprecipitation, bimolecular fluorescence complementation and microscale thermophoresis. Our findings supported that CaWRKY28 is a nuclear protein that acts as positive regulator in pepper responses to the pathogenic bacterium Ralstonia solanacearum infection. It performs its function not by directly modulating the W-box containing immunity related genes but by promoting CaWRKY40 via physical interaction to bind and activate its immunity related target genes including CaPR1, CaNPR1, CaDEF1 and CaABR1, but not its thermotolerance related target gene CaHSP24. All these data indicate that CaWRKY28 interacts with and potentiates CaWRKY40 in regulating immunity against R. solanacearum infection but not thermotolerance. Importantly, we discovered that CaWRKY28 Cys249, shared by CaWRKY28 and its orthologs probably only in the Solanaceae, is crucial for the CaWRKY28-CaWRKY40 interaction. These results highlight how CaWRKY28 associates with CaWRKY40 during the establishment of WRKY networks, and how CaWRKY40 achieves its functional specificity during pepper responses to R. solanacearum infection.

7.
J Tradit Chin Med ; 41(1): 36-43, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33522195

RESUMO

OBJECTIVE: To investigate the efficacy of the extract from Yiyuan Yiliu Tang (, YYYLT) on human lung adenocarcinoma cells A549 and human hepatoma cells Bel7402. METHODS: The cancer cell lines were treated with various concentrations (0, 100, 200, 300, and 400 µg/mL) of the crude water extract of YYYLT and then cell viability, toxicity, cytokine secretion, and cell cycle/apoptosis were determined by MTT assay, LDH assay, and flow cytometry, respectively. RESULTS: The extract from YYYLT significantly suppressed the proliferation of the cancer cell lines and the release of interleukin-2 and tumor necrosis factor-α in a dose-dependent manner. The extract also promoted apoptosis, caused cell cycle arrest at G0/G1 phase, and increased the expression of caspase-3, B-cell lymphoma-2 (Bcl-2), and Bcl-2-associated X proteins. CONCLUSION: The extract from YYYLT might be a potential treatment for human lung and liver cancers.

8.
Science ; 371(6528)2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33509998

RESUMO

Spectroscopic analysis is one of the most widely used analytical tools in scientific research and industry. Although laboratory benchtop spectrometer systems offer superlative resolution and spectral range, their miniaturization is crucial for applications where portability is paramount or where in situ measurements must be made. Advancement in this field over the past three decades is now yielding microspectrometers with performance and footprint near those viable for lab-on-a-chip systems, smartphones, and other consumer technologies. We summarize the technologies that have emerged toward achieving these aims-including miniaturized dispersive optics, narrowband filter systems, Fourier transform interferometers, and reconstructive microspectrometers-and discuss the challenges associated with improving spectral resolution while device dimensions shrink ever further.

9.
Rev Sci Instrum ; 92(1): 015111, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33514201

RESUMO

Modern imaging techniques increasingly require signals to be collected from multiple viewpoints and spectral bands to realize multi-dimensional and multi-species detections. For this purpose, multiple cameras are commonly required. Each camera collects signals from one viewpoint or one spectral band, resulting in a considerable experimental cost. Based on frequency modulation, this work proposes an encoded-imaging technique that can record multangular and multispectral images in one acquisition. The signals recorded from different viewpoints and spectral bands are superimposed in the spatial domain, while being separate in the frequency domain. This allows us to extract individual images based on their respective frequency components. In this work, a proof-of-concept experiment was conducted. The high correlation coefficient between the superimposition of the extracted images and a normal superimposed image demonstrates the effectiveness of this technique. In addition, an improved mathematical formulation was proposed to describe the higher spatial-frequency components, which were considered merely to be residual lines in previous studies. The proposed encoded-imaging technique may have potential for multangular and multispectral imaging, which is especially useful for tomographic reconstructions.

10.
Nano Lett ; 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33411539

RESUMO

Corrosion of metals in atmospheric environments is a worldwide problem in industry and daily life. Traditional anticorrosion methods including sacrificial anodes or protective coatings have performance limitations. Here, we report atomically thin, polycrystalline few-layer graphene (FLG) grown by chemical vapor deposition as a long-term protective coating film for copper (Cu). A six-year old, FLG-protected Cu is visually shiny and detailed material characterizations capture no sign of oxidation. The success of the durable anticorrosion film depends on the misalignment of grain boundaries between adjacent graphene layers. Theoretical calculations further found that corrosive molecules always encounter extremely high energy barrier when diffusing through the FLG layers. Therefore, the FLG is able to prevent the corrosive molecules from reaching the underlying Cu surface. This work highlights the interesting structures of polycrystalline FLG and sheds insight into the atomically thin coatings for various applications.

11.
Chem Commun (Camb) ; 57(7): 903-906, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33367330

RESUMO

Co, N co-doped carbon (CoN@C) with properly engineered heteropores was facilely synthesized using metal carbonate hydroxides as metal precursor and multistage porogen. CoN@C therefore exhibits superior ORR catalytic activity with a half-wave potential of 0.876 V vs. RHE, and the CoN@C-based zinc-air battery can be stably cycled for 100 h.

12.
Environ Res ; 192: 110261, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32997967

RESUMO

The question of how to reasonably dispose and recycle antibiotic mycelial residues (AMRs), a hazardous waste, is a critical issue. The AMRs containing nitrogen-rich organic matters shows a promising alternative feedstock of nitrogen-doped porous carbons (NPCs). Here, the NPCs with the ultrahigh surface area (2574.9 m2 g-1) were prepared by using the discarded oxytetracycline mycelial residues (OMRs) and further used as an electrode for supercapacitor. A series of experiments including scanning/transmission electron microscope, Brunauer-Emmett-Teller measurement, and electrochemical impedance spectrum revealed that the NPC-2-900 exhibited a high N content, large surface area, and high electrical conductivity. The electrochemical performance of the NPC was tested by cyclic voltammetry, galvanostatic charge/discharge cycling, and rate capability test. The optimized NPC-2-900 displayed distinguish specific capacitance (307 F g-1), cycling stability (over 95% capacitance retention after 2000 cycles even at a high current density of 20 A g-1) and superior rate performance. Of particular interest, the qPCR test indicates the ARGs were reduced in the conversion process from OMRs to NPCs.


Assuntos
Carbono , Nitrogênio , Antibacterianos , Resistência Microbiana a Medicamentos , Porosidade
14.
Int J Biol Macromol ; 2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33122060

RESUMO

Wound healing is a complex, dynamic and difficult process. Much effort and attempt has been made to accelerate this process. The purpose of this study is to prepare nanoparticles loaded with vaccarin (VAC-NPS)hydrogel and evaluate its effect on promoting wound healing. In the present study, the physicochemical properties of VAC-NPS were characterized. Transmission electron microscopy (TEM) was used to observe the morphology of VAC-NPS. Human umbilical vein endothelial cells (HUVEC) was employed to assessment the biocompatibility of VAC-NPS in vitro. The wound healing function of VAC-NPS hydrogels was evaluated in the full-thickness dermal wound in a rat model. The results indicated that VAC-NPS was spherical like particles with uniform particle size distribution and no obvious aggregation with a diameter of (216.6 ±â€¯10.1)nm. The loading capacity and encapsulation efficiency of VAC in the nanoparticles were (14.3 ±â€¯1.2) % and (51.7 ±â€¯1.7) % respectively. MTT assay demonstrated that the VAC-NPS had no cytotoxicity and could promote HUVEC proliferation and migration. In vivo results showed that VAC-NPS promotes wound healing, and the mechanism may be through up-regulating IL-1ß and PDGF-BB, promoting angiogenesis. VAC-NPS might have a potential application value for the treatment of the wound healing and a promising performance in bio-medically relevant systems.

15.
ACS Chem Biol ; 15(9): 2605-2615, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32909734

RESUMO

Type II collagen (CII) is the most abundant protein in joint cartilage. Antibodies to CII appear around the clinical onset of the autoimmune disease rheumatoid arthritis (RA) in a subset of patients. They target specific epitopes on CII and can be pathogenic or protective. Assays for early detection of such autoantibodies may provide new opportunities for selecting effective treatment strategies of RA. We report the efficient and reproducible assembly of an array of covalently branched native and citrullinated triple helical peptides (THPs) from CII that contain defined autoantibody epitopes. Both monoclonal antibodies and sera from experimental mouse models show a unique reactivity toward the THPs, compared to cyclic peptides containing the epitopes, revealing the importance that the epitopes are displayed in a triple-helical conformation. Importantly, antibodies against three of the THPs that contain major CII epitopes were found to be increased in sera from patients with RA, compared to control persons. These results indicate that such synthetic THPs should be included in multiplex analysis of autoantibodies that are uniquely occurring in individuals with early RA, to provide valuable information on disease prognosis and on what type of therapy should be chosen for individual patients.

16.
Chem Commun (Camb) ; 56(81): 12214-12217, 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-32926015

RESUMO

A facile boron doping strategy to improve the nitrogen retention in carbon-based catalysts is developed toward efficient oxygen reduction reaction via offsetting the electron migration. By considering the hetero-porous structure at the same time, this B, N co-doped catalyst outperforms commercial Pt/C in terms of both activity and stability.

17.
Inflamm Res ; 69(11): 1087-1101, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32797249

RESUMO

PURPOSE: Rheumatoid arthritis (RA) is a chronic, systemic autoimmune disease with synovitis as pathological changes. The immune microenvironment of RA promotes metabolic reprogramming of immune cells and stromal cells, which leads to dysfunction and imbalance of immune homeostasis. Cell metabolism undergoes the switch from a static regulatory state to a highly metabolic active state, which changes the redox-sensitive signaling pathway and also leads to the accumulation of metabolic intermediates, which in turn can act as signaling molecules and further aggravate the inflammatory response. The reprogramming of immunometabolism affects the function of immune cells and is crucial to the pathogenesis of RA. In addition, mitochondrial dysfunction plays a key role in glycolytic reprogramming in RA. These metabolic changes may be potential therapeutic targets for RA. Therefore, we reviewed the metabolic reprogramming of RA immune cells and fibroblast-like synovium cells (FLS) and its relationship with mitochondrial dysfunction. METHODS: A computer-based online search was performed using the PubMed database and Web of Science database for published articles concerning immunometabolic reprogramming, mitochondrial dysfunction, and rheumatoid arthritis. RESULTS: This article reviews the metabolic reprogramming of immune cells and fibroblast-like synoviocytes in RA and their relationship to mitochondrial disfunction, as well as the key pro-inflammatory pathways associated with metabolic reprogramming and chemotherapy as a potential future therapeutic strategy for RA.

18.
Int Immunopharmacol ; 87: 106830, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32738596

RESUMO

Berberine (BBR) is the effective constituent of Cortex phellodendri and was characterized as an excellent anti-microbial agent with significant anti-inflammatory effects. Previously, we had demonstrated that BBR alleviated the inflammatory response in adjuvant-induced arthritis (AA) rats by regulating polarization of macrophages. However, the exact mechanics by which BBR regulates macrophage polarization remained unclear. Here, we showed that BBR treatment had little influence on total number of macrophages in joints of AA rats, but increased the proportion of M2 macrophages and decreased the proportion of M1 macrophages. Meanwhile, we found BBR up-regulated the expression of AMP-activated protein kinase phosphorylation (p-AMPK) and down-regulated the expression of Hypoxia inducible factor 1α (HIF-1α) in synovial macrophages of AA rats. In vitro, using LPS-stimulated peritoneal macrophages from normal rats, we also verified that pretreatment with BBR promoted transition from M1 to M2 by up-regulating the expression of p-AMPK and suppressing the expression of HIF-1α. Compound C (an AMPK inhibitor) could abrogate the inhibition of BBR on migration of macrophages. Glycolysis of M1 suppressed by BBR through decreasing lactate export, glucose consumption, and increasing intracellular ATP content, which was remarkably reversed by Compound C. These findings indicated that anti-arthritis effect of BBR is associated with regulating energy metabolism of macrophages through AMPK/HIF-1α pathway.

19.
Opt Lett ; 45(14): 3957-3960, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32667327

RESUMO

Two-line atomic fluorescence (TLAF) is a promising technique for two-dimensional (2D) flame thermometry. However, it suffers either from a low signal-to-noise ratio (SNR) when excited in the linear regime or a quenching effect and nonlinear behavior in the nonlinear regime. This work aims to develop a new TLAF modality, which can overcome the aforementioned limitations based on a specifically designed laser source that can generate long pulses (∼400ns) with a moderate energy of ∼0.9µJ and operate at a repetition rate up to ∼22kHz. A proof-of-concept experiment was conducted and linearly excited fluorescence images with an SNR up to ∼14 were obtained within 1 ms acquisition time by synchronizing the laser with the microchannel plate (MCP) of a 10 Hz-rate intensified camera. The SNR achieved was comparable to that of a traditional nonlinear TLAF implementation and superior to a conventional linear TLAF approach. This approach offers a novel solution for recording linearly excited indium fluorescence images and is expected to make TLAF a temporally resolved and high-precision 2D thermometry for the first time.

20.
Appl Environ Microbiol ; 86(17)2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32561585

RESUMO

Hydrogen-entangled electron transfer has been verified as an important extracellular pathway of sharing reducing equivalents to regulate biofilm activities within a diversely anaerobic environment, especially in microbial electrosynthesis systems. However, with a lack of useful methods for in situ hydrogen detection in cathodic biofilms, the role of hydrogen involvement in electron transfer is still debatable. Here, a cathodic biofilm was constructed in CH4-produced microbial electrosynthesis reactors, in which the hydrogen evolution dynamic was analyzed to confirm the presence of hydrogen-associated electron transfer near the cathode within a micrometer scale. Fluorescent in situ hybridization images indicated that a colocalized community of archaea and bacteria developed within a 58.10-µm-thick biofilm at the cathode, suggesting that the hydrogen gradient detected by the microsensor was consumed by the collaboration of bacteria and archaea. Coupling of a microsensor and cyclic voltammetry test further provided semiquantitative results of the hydrogen-associated contribution to methane generation (around 21.20% ± 1.57% at a potential of -0.5 V to -0.69 V). This finding provides deep insight into the mechanism of electron transfer in biofilm on conductive materials.IMPORTANCE Electron transfer from an electrode to biofilm is of great interest to the fields of microbial electrochemical technology, bioremediation, and methanogenesis. It has a promising potential application to boost more value-added products or pollutant degradation. Importantly, the ability of microbes to obtain electrons from electrodes and utilize them brings new insight into direct interspecies electron transfer during methanogenesis. Previous studies verified the direct pathway of electron transfer from the electrode to a pure-culture bacterium, but it was rarely reported how the methanogenic biofilm of mixed cultures shares electrons by a hydrogen-associated or hydrogen-free pathway. In the current study, a combination method of microsensor and cyclic voltammetry successfully semiquantified the role of hydrogen in electron transfer from an electrode to methanogenic biofilm.


Assuntos
Archaea/fisiologia , Fenômenos Fisiológicos Bacterianos , Biofilmes , Hidrogênio/metabolismo , Metano/metabolismo , Archaea/metabolismo , Bactérias/metabolismo , Transporte de Elétrons
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