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1.
J Virol ; : e0060624, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38809020

RESUMEN

Rabies virus (RABV) is highly lethal and triggers severe neurological symptoms. The neuropathogenic mechanism remains poorly understood. Ras-related C3 botulinum toxin substrate 1 (Rac1) is a Rho-GTPase that is involved in actin remodeling and has been reported to be closely associated with neuronal dysfunction. In this study, by means of a combination of pharmacological inhibitors, small interfering RNA, and specific dominant-negatives, we characterize the crucial roles of dynamic actin and the regulatory function of Rac1 in RABV infection, dominantly in the viral entry phase. The data show that the RABV phosphoprotein interacts with Rac1. RABV phosphoprotein suppress Rac1 activity and impedes downstream Pak1-Limk1-Cofilin1 signaling, leading to the disruption of F-actin-based structure formation. In early viral infection, the EGFR-Rac1-signaling pathway undergoes a biphasic change, which is first upregulated and subsequently downregulated, corresponding to the RABV entry-induced remodeling pattern of F-actin. Taken together, our findings demonstrate for the first time the role played by the Rac1 signaling pathway in RABV infection and may provide a clue for an explanation for the etiology of rabies neurological pathogenesis.IMPORTANCEThough neuronal dysfunction is predominant in fatal rabies, the detailed mechanism by which rabies virus (RABV) infection causes neurological symptoms remains in question. The actin cytoskeleton is involved in numerous viruses infection and plays a crucial role in maintaining neurological function. The cytoskeletal disruption is closely associated with abnormal nervous symptoms and induces neurogenic diseases. In this study, we show that RABV infection led to the rearrangement of the cytoskeleton as well as the biphasic kinetics of the Rac1 signal transduction. These results help elucidate the mechanism that causes the aberrant neuronal processes by RABV infection and may shed light on therapeutic development aimed at ameliorating neurological disorders.

2.
Plant Cell ; 32(5): 1397-1413, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32102844

RESUMEN

Maize (Zea mays) is one of the most important crops in the world. However, few agronomically important maize genes have been cloned and used for trait improvement, due to its complex genome and genetic architecture. Here, we integrated multiplexed CRISPR/Cas9-based high-throughput targeted mutagenesis with genetic mapping and genomic approaches to successfully target 743 candidate genes corresponding to traits relevant for agronomy and nutrition. After low-cost barcode-based deep sequencing, 412 edited sequences covering 118 genes were precisely identified from individuals showing clear phenotypic changes. The profiles of the associated gene-editing events were similar to those identified in human cell lines and consequently are predictable using an existing algorithm originally designed for human studies. We observed unexpected but frequent homology-directed repair through endogenous templates that was likely caused by spatial contact between distinct chromosomes. Based on the characterization and interpretation of gene function from several examples, we demonstrate that the integration of forward and reverse genetics via a targeted mutagenesis library promises rapid validation of important agronomic genes for crops with complex genomes. Beyond specific findings, this study also guides further optimization of high-throughput CRISPR experiments in plants.


Asunto(s)
Proteína 9 Asociada a CRISPR/metabolismo , Sistemas CRISPR-Cas/genética , Genes de Plantas , Mutagénesis/genética , Carácter Cuantitativo Heredable , Zea mays/genética , Secuencia de Bases , Reparación del ADN/genética , Edición Génica , Mutación/genética , Plantas Modificadas Genéticamente , Plásmidos/genética , ARN Guía de Kinetoplastida/genética , Reproducibilidad de los Resultados , Moldes Genéticos , Transformación Genética
3.
Analyst ; 148(19): 4659-4667, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37615041

RESUMEN

We report a fully integrated digital microfluidic absorbance detection system with an enhanced sensitivity for online bacterial monitoring. Through a 100 µm gap in the chip, our optical detection system has a detection sensitivity for a BCA protein concentration of 0.1 mg mL-1. The absorbance detection limit of our system is 1.4 × 10-3 OD units, which is one order of magnitude better than that of the existing studies. The system's linear region is 0.1-7 mg mL-1, and the dynamic range is 0-25 mg mL-1. We measured the growth curves of wild-type and E. coli transformed with resistance plasmids and mixed at different ratios on chip. We sorted out the bacterial species including highly viable single cells based on the difference in absorbance data of growth curves. We explored the changes in the growth curves of E. coli under different concentrations of resistant media. In addition, we successfully screened for the optimal growth environment of the bacteria, in which the growth rate of PET30a-DH5α (in a medium with 33 µg mL-1 kanamycin resistance) was significantly higher than that of a 1 mg mL-1 resistance medium. In conclusion, the enhanced digital microfluidic absorbance detection system exhibits exceptional sensitivity, enabling precise bacterial monitoring and growth curve analysis, while also laying the foundation for DMF-based automated bioresearch platforms, thus advancing research in the life sciences.


Asunto(s)
Microfluídica , Dispositivos Ópticos , Escherichia coli , Dispositivos Laboratorio en un Chip , Movimiento Celular
4.
Nanotechnology ; 35(9)2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38029450

RESUMEN

As an ultra-wide bandgap semiconductor, gallium oxide (Ga2O3) has been extensively applied in solar-blind photodetectors (PDs) owing to the absorbance cut-off wavelength of shorter than 280 nm, and the optimized technologies of detection performance is seriously essential for its further usages. Herein, a feasible thermal reorder engineering method was performed through annealing Ga2O3films in vacuum, O2and oxygen plasma atmospheres, realizing to tune solar-blind photosensing performance of Ga2O3PDs. Thermal treatment, in fact a crystal reorder process, significantly suppressed the noise in Ga2O3-based PDs and enhanced the photo-sensitivity, with the dark current decreasing from 154.63 pA to 269 fA and photo-to-dark current ratio magically raising from 288 to 2.85 × 104. This achievement is dependent of energy-band modulation in Ga2O3semiconductor, that is certified by first-principles calculation. Additionally, annealing in oxygen atmospheres notably reduces the concentration of oxygen vacancies in the surface of films, thereby improving the performance of the PDs; the oxygen vacancy is extremely concerned in oxide semiconductors in the view of physics of surface defects. In all, this work could display a promising guidance for modulating the performance of PDs based on wide bandgap oxide semiconductor, especially for hot Ga2O3issue.

5.
Plant Biotechnol J ; 20(3): 526-537, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34687251

RESUMEN

Maize height is determined by the number of nodes and the length of internodes. Node number is driven by intercalary meristem formation and internode length by intercalary cell elongation, respectively. However, mechanisms regulating establishment of nodes and internode growth are unclear. We screened EMS-induced maize mutants and identified a dwarf mutant zm66, linked to a single base change in TERMINAL EAR 1 (ZmTE1). Detailed phenotypic analysis revealed that zm66 (zmte1-2) has shorter internodes and increased node numbers, caused by decreased cell elongation and disordered intercalary meristem formation, respectively. Transcriptome analysis showed that auxin signalling genes are also dysregulated in zmte1-2, as are cell elongation and cell cycle-related genes. This argues that ZmTE1 regulates auxin signalling, cell division, and cell elongation. We found that the ZmWEE1 kinase phosphorylates ZmTE1, thus confining it to the nucleus and probably reducing cell division. In contrast, the ZmPP2Ac-2 phosphatase promotes dephosphorylation and cytoplasmic localization of ZmTE1, as well as cell division. Taken together, ZmTE1, a key regulator of plant height, is responsible for maintaining organized formation of internode meristems and rapid cell elongation. ZmWEE1 and ZmPP2Ac-2 might balance ZmTE1 activity, controlling cell division and elongation to maintain normal maize growth.


Asunto(s)
Meristema , Zea mays , Ciclo Celular , Regulación de la Expresión Génica de las Plantas/genética , Ácidos Indolacéticos , Meristema/genética , Zea mays/genética
6.
J Med Virol ; 94(2): 557-566, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-30968963

RESUMEN

Although the expression of thousands of host long noncoding RNAs (lncRNAs) can be regulated by viral infection, the number of lncRNAs with experimentally verified function is limited. In this study, the expression of host lncRNA TSPOAP1-AS1 was significantly induced by influenza A virus (IAV) infection in a dose- and time-dependent manner. Polyinosine-polycytidylic acid (poly (I:C)), a synthetic analog of double-stranded RNA, also increased TSPOAP1-AS1 expression. RNA fractionation revealed that TSPOAP1-AS1 was a nucleocytoplasmic lncRNA, and an increased nuclear/cytoplasmic ratio was detected after IAV infection. The nuclear factor-κB signaling acting as a critical factor in the transcription of TSPOAP1-AS1 was determined through the use of pharmacological and genetic approaches. Functionally, overexpression of TSPOAP1-AS1 resulted in a significant increase in IAV replication. In contrast, the abolition of TSPOAP1-AS1 by RNA interference restricted viral replication. Furthermore, we demonstrated that TSPOAP1-AS1 negatively modulated the IAV-induced Ifnb1 transcription, interferon-sensitive response element (ISRE) activation, and downstream interferon-stimulated genes expression. Collectively, our data provides evidence for the host lncRNA utilized by viruses to support its replication.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Virus de la Influenza A/fisiología , Interferón Tipo I/metabolismo , ARN Largo no Codificante/genética , Replicación Viral/efectos de los fármacos , Células A549 , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Gripe Humana/genética , Gripe Humana/virología , Interferones , FN-kappa B/metabolismo , Poli I-C/farmacología , Interferencia de ARN , ARN sin Sentido/farmacología , Transducción de Señal/efectos de los fármacos
7.
Crit Rev Food Sci Nutr ; : 1-15, 2022 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-36218372

RESUMEN

Food allergy has become a major public health problem all over the world. Evidence showed that allergic reactions induced by food proteins often lead to disturbances in the gut microbiota (symbiotic bacteria). Gut microbiota plays an important role in maintaining the balance between intestinal immune tolerance and allergic reactions. Dietary intervention has gradually become an important method for the prevention and treatment of allergic diseases, and changing the composition of gut microbiota through oral intake of prebiotics and probiotics may serve as a new effective adjuvant treatment measure for allergic diseases. In this paper, the main mechanism of food allergy based on intestinal immunity was described firstly. Then, the clinical and experimental evidence showed that different prebiotics and probiotics affect food allergy by changing the structure and composition of gut microbiota was summarized. Moreover, the molecular mechanism in which the gut microbiota and their metabolites may directly or indirectly regulate the immune system or intestinal epithelial barrier function to affect food immune tolerance of host were also reviewed to help in the development of food allergy prevention and treatment strategies based on prebiotics and probiotics.

8.
Int J Mol Sci ; 22(13)2021 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-34281250

RESUMEN

Amelogenin comprises ~90% of enamel proteins; however, the involvement of Amelx transcriptional activation in regulating ameloblast differentiation from induced pluripotent stem cells (iPSCs) remains unknown. In this study, we generated doxycycline-inducible Amelx-expressing mouse iPSCs (Amelx-iPSCs). We then established a three-stage ameloblast induction strategy from Amelx-iPSCs, including induction of surface ectoderm (stage 1), dental epithelial cells (DECs; stage 2), and ameloblast lineage (stage 3) in sequence, by manipulating several signaling molecules. We found that adjunctive use of lithium chloride (LiCl) in addition to bone morphogenetic protein 4 and retinoic acid promoted concentration-dependent differentiation of DECs. The resulting cells had a cobblestone appearance and keratin14 positivity. Attenuation of LiCl at stage 3 together with transforming growth factor ß1 and epidermal growth factor resulted in an ameloblast lineage with elongated cell morphology, positivity for ameloblast markers, and calcium deposition. Although stage-specific activation of Amelx did not produce noticeable phenotypic changes in ameloblast differentiation, Amelx activation at stage 3 significantly enhanced cell adhesion as well as decreased proliferation and migration. These results suggest that the combination of inducible Amelx transcription and stage-specific ameloblast induction for iPSCs represents a powerful tool to highlight underlying mechanisms in ameloblast differentiation and function in association with Amelx expression.


Asunto(s)
Ameloblastos/citología , Ameloblastos/metabolismo , Amelogenina/metabolismo , Ameloblastos/fisiología , Amelogenina/genética , Animales , Adhesión Celular/fisiología , Diferenciación Celular/fisiología , Doxiciclina/farmacología , Células Epiteliales/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Ratones , Transducción de Señal , Activación Transcripcional/fisiología
9.
Jpn J Clin Oncol ; 50(4): 387-391, 2020 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-31829423

RESUMEN

BACKGROUND: Remote access and endoscopic thyroid surgery has been gaining popularity because it allows patients to avoid a visible scar in the neck. There is limited data on transoral endoscopic thyroidectomy when it relates to patients with papillary thyroid carcinoma. We aim to evaluate the safety of ipsilateral central compartment dissection for patients who undergo transoral thyroidectomy (thyroidectomy vestibular approach-compartment lymph node dissection). PATIENTS AND METHODS: A total of 80 patients who underwent thyroidectomy vestibular approach-compartment lymph node dissection for papillary thyroid carcinoma from June 2015 to September 2016 were identified. Over the same period, a matched cohort of 80 patients who underwent open thyroidectomy with routine ipsilateral central compartment dissection was also identified (Open-compartment lymph node dissection). The two groups were analyzed in terms of patient characteristics, perioperative clinical results and post-operative outcomes. RESULTS: All patients were female with a mean age of 32-year. There was no difference in mean maximum tumor size and number of lymph nodes dissected. Moreover, there was no difference in average positive lymph nodes between thyroidectomy vestibular approach-compartment lymph node dissection and Open-compartment lymph node dissection (1.48 vs 1.08, P = 0.647). Operative time was longer in the thyroidectomy vestibular approach-compartment lymph node dissection group (193 vs 102 min, P < 0.001). Thyroidectomy specific complications were similar with rates of temporary recurrent laryngeal nerve palsy of 6.3 vs 8.8% and temporary hypocalcemia rates of 2.5 vs 5% in the thyroidectomy vestibular approach-compartment lymph node dissection and Open-compartment lymph node dissection groups, respectively. CONCLUSIONS: Thyroidectomy vestibular approach-compartment lymph node dissection is a feasible and safe option for select patients with papillary thyroid carcinoma who require central node dissection compared with Open-compartment lymph node dissection, and can be a viable alternative for patients wishing to avoid a visible scar.


Asunto(s)
Carcinoma Papilar/cirugía , Endoscopía , Boca/cirugía , Disección del Cuello/efectos adversos , Neoplasias de la Tiroides/cirugía , Adulto , Carcinoma Papilar/patología , Femenino , Humanos , Persona de Mediana Edad , Cáncer Papilar Tiroideo , Neoplasias de la Tiroides/patología , Adulto Joven
10.
Int J Mol Sci ; 21(2)2020 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-31963264

RESUMEN

Cell condensation and mechanical stimuli play roles in osteogenesis and chondrogenesis; thus, they are promising for facilitating self-organizing bone/cartilage tissue formation in vitro from induced pluripotent stem cells (iPSCs). Here, single mouse iPSCs were first seeded in micro-space culture plates to form 3-dimensional spheres. At day 12, iPSC spheres were subjected to shaking culture and maintained in osteogenic induction medium for 31 days (Os induction). In another condition, the osteogenic induction medium was replaced by chondrogenic induction medium at day 22 and maintained for a further 21 days (Os-Chon induction). Os induction produced robust mineralization and some cartilage-like tissue, which promoted expression of osteogenic and chondrogenic marker genes. In contrast, Os-Chon induction resulted in partial mineralization and a large area of cartilage tissue, with greatly increased expression of chondrogenic marker genes along with osterix and collagen 1a1. Os-Chon induction enhanced mesodermal lineage commitment with brachyury expression followed by high expression of lateral plate and paraxial mesoderm marker genes. These results suggest that combined use of micro-space culture and mechanical stimuli facilitates hybrid bone/cartilage tissue formation from iPSCs, and that the bone/cartilage tissue ratio in iPSC constructs could be manipulated through the induction protocol.


Asunto(s)
Cartílago/química , Células Madre Pluripotentes Inducidas/citología , Animales , Células Cultivadas , Colágeno/metabolismo , Proteínas Fetales/metabolismo , Ratones , Osteogénesis/genética , Osteogénesis/fisiología , Factor de Transcripción Sp7/genética , Factor de Transcripción Sp7/metabolismo , Proteínas de Dominio T Box/metabolismo
11.
Anal Chem ; 91(20): 13054-13061, 2019 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-31539227

RESUMEN

Ancient Chinese sauce glaze porcelain has recently received growing attention for the discovery of epsilon iron oxide (ε-Fe2O3) crystals in glaze. In this work, we first confirm the presence of ε-Fe2O3 microcrystals, in large quantiteis, in sauce glaze porcelain fired at the Qilizhen kiln in Jiangxi province during the Southern Song dynasty. We then employed focused ion beam scanning electron microscopy (FIB-SEM) to investigate the three-dimensional microstructure of ε-Fe2O3 microcrystals, which revealed three well-separated layers (labeled, respectively, as LY1, LY2, and LY3 from the glaze surface to inside) under the glaze surface. Specifically, LY1 consists of well-defined dendritic fractal structure with high ordered branches at micrometers scale, LY2 has spherical or irregular-shaped particles at nanometers scale, while LY3 consists of dendrites with four, six, or eight primary branches ranging from several nanometers to around 1 µm. Given these findings, we proposed a process for the possible growth of ε-Fe2O3 microcrystals in ancient Chinese sauce glaze.

12.
Plant Physiol ; 177(2): 819-832, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29720555

RESUMEN

Auxin has been shown to enhance root growth inhibition under aluminum (Al) stress in Arabidopsis (Arabidopsis thaliana). However, in maize (Zea mays), auxin may play a negative role in the Al-induced inhibition of root growth. In this study, we identified mutants deficient in the maize auxin efflux carrier P-glycoprotein (ZmPGP1) after ethyl methanesulfonate mutagenesis and used them to elucidate the contribution of ZmPGP1 to Al-induced root growth inhibition. Root growth in the zmpgp1 mutant, which forms shortened roots and is hyposensitive to auxin, was less inhibited by Al stress than that in the inbred line B73. In the zmpgp1 mutants, the root tips displayed higher auxin accumulation and enhanced auxin signaling under Al stress, which was also consistent with the increased expression of auxin-responsive genes. Based on the behavior of the auxin-responsive marker transgene, DR5rev:RFP, we concluded that Al stress reduced the level of auxin in the root tip, which contrasts with the tendency of Al stress-induced Arabidopsis plants to accumulate more auxin in their root tips. In addition, Al stress induced the expression of ZmPGP1 Therefore, in maize, Al stress is associated with reduced auxin accumulation in root tips, a process that is regulated by ZmPGP1 and thus causes inhibition of root growth. This study provides further evidence about the role of auxin and auxin polar transport in Al-induced root growth regulation in maize.


Asunto(s)
Aluminio/toxicidad , Ácidos Indolacéticos/metabolismo , Proteínas de Plantas/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Zea mays/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Meristema/efectos de los fármacos , Meristema/genética , Meristema/metabolismo , Mutación , Ácidos Naftalenoacéticos/farmacología , Proteínas de Plantas/genética , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Plantas Modificadas Genéticamente , Transducción de Señal , Zea mays/genética , Zea mays/crecimiento & desarrollo , Zea mays/metabolismo
13.
Virol J ; 16(1): 80, 2019 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-31196105

RESUMEN

BACKGROUND: Rabies virus (RABV), a member of Lyssavirus of Rhabdoviridae family, is a kind of negative-strand RNA virus. The zoonosis caused by RABV leads to high mortality in animals and humans. Though with the extensive investigation, the mechanisms of RABV entry into cells have not been well characterized. METHODS: Chemical inhibitors and RNA interference (RNAi) were used to analysis RABV internalization pathway. The expression level of viral N protein was examined by quantitative PCR and western blot, and the virus infection in the cells was visualized by fluorescence microscopy. RESULTS: We firstly examined the endocytosis pathway of the challenge virus standard (CVS) -11 strain in N2a cells. Chlorpromazine treatment and knockdown of clathrin heavy chain (CHC) significantly reduced viral entry, which proved clathrin was required. Meanwhile neither nystatin nor knocking down caveolin-1 (Cav1) in N2a cells had an effect on CVS-11 infection, suggesting that caveolae was independent for CVS-11 internalization. And when cholesterol of cell membrane was extracted by MßCD, viral infection was strongly impacted. Additionally by using the specific inhibitor dynasore and ammonium chloride, we verified that dynamin and a low-pH environment were crucial for RABV infection, which was confirmed by confocal microscopy. CONCLUSIONS: Our results demonstrated that CVS-11 entered N2a cells through a clathrin-mediated, cholesterol-, pH-, dynamin-required, and caveolae-independent endocytic pathway.


Asunto(s)
Colesterol/metabolismo , Clatrina/metabolismo , Dinaminas/metabolismo , Endocitosis , Virus de la Rabia/fisiología , Internalización del Virus , Línea Celular , Clorpromazina/farmacología , Concentración de Iones de Hidrógeno , Proteínas de la Nucleocápside/genética , Interferencia de ARN , Virus de la Rabia/efectos de los fármacos
14.
Langmuir ; 35(29): 9504-9512, 2019 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-31256592

RESUMEN

The ability to make stable water-in-oil (W/O) Pickering high internal phase emulsions (HIPEs) is demonstrated using microcapsules as a stabilizer. The microcapsules are prepared with glycidyl methacrylate (GMA) and poly(melamine-formaldehyde) (PMF) as core and wall materials, respectively. Using these GMA-loaded PMF-walled microcapsules as a sole stabilizer of water-in-styrene/divinylbenzene HIPE, the polymerization of this HIPE causes a closed-cell porous polymer. While with the addition of a certain amount of the nonionic surfactant Span80 to the microcapsule-stabilized HIPEs, a series of open-cell porous materials are obtained. The morphologies of the porous materials are tunable with changing the microcapsules content and/or surfactant amount in the HIPE templates. When Raft polymerization is introduced to cure these HIPEs, owing to both the self-healing agent GMA within the microcapsules and the residue of the chain-transfer agent from Raft polymerization of HIPEs, the resulting porous polymers are proved to be self-repairable. This work suggests a new type of Pickering HIPE and provides a novel idea for preparing self-healing porous materials.

15.
Inorg Chem ; 58(12): 7947-7957, 2019 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-31185555

RESUMEN

The mixed hexa-transition metal (hexa-TM) sandwiched arsenotungstate derivative, [CuI3(pz)2(phen)3]2[CuI(phen)2][{Na(H2O)2}{(VIV5CuIIO6)(AsIIIW9O33)2}]·6H2O (1) (pz = pyrazine; phen = 1,10-phenanthroline), has been hydrothermally synthesized and structurally characterized. In compound 1, two {AsW9O33} clusters are connected by mixed hexa-TM ring unit {VVI5CuIIO6} to form a sandwich-type dimer, which are further bonded in "ABAB" mode by the {Na(H2O)2} linker resulting in pure inorganic chains. The unique "L-shaped" trinuclear complex {Cu3(phen)3(pz)2} is supported together via staggered π-π interactions to generate extending waveform two-dimensional supramolecular layers, which are further aggregated with their adjacent analogues by complexes {Cu(phen)2} via H-bonding interaction to yield an unprecedented three-dimensional (3D) metal-organic networks with one-dimensional (1D) cavities. The pure inorganic 1D sandwich chains are implanted in the cavities as guest units via supramolecular interactions to form a POMOF 3D framework. Compound 1, as the electrode of the supercapacitor, exhibits higher specific capacitances (825 F g-1 at a current density of 2.4 A g-1), better rate capability, more durable cyclic stability (91.4% of cycle efficiency after 3000 cycles), and improved conductivity and electroactivity compared to those of parent polyoxometalate (POM) Na9[AsW9O33]·19H2O (2) and 6-Cu-substituted POM [Cu6(imi)6{AsIIIW9O30Cl3}2]·6H2O (3), which may be attributed to the introduction of V4+, the unique host-guest structure, and the rich π electron system. In addition, compound 1 exhibits dual-function electrocatalytic behavior in reducing inorganic salt IO3- and oxidizing the organic molecule dopamine.

16.
J Nanosci Nanotechnol ; 19(8): 5338-5343, 2019 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-30913853

RESUMEN

The counter electrode (CE) with high catalytic activity has been vital to improve photovoltaic performance of quantum dot sensitized solar cells (QDSSCs). Cobalt selenide has been proved to have outstanding electrocatalytic activity among the electrode materials. In this work, Co0.85Se films were directly deposited on the F doped SnO2 glass (FTO) substrate by one-step solvothermal method. The film phase and microstructure were characterized by X-ray diffraction (XRD) and high-resolution transmission electron microscopy (TEM), respectively. Further, the effects of starting reactant concentration on the uniformity and continuity of Co0.85Se films were determined by scanning electron microscope (SEM) and energy-dispersive spectrometer (EDS). Then, QDSSCs with Co0.85Se film as CE and CdS/CdSe/TiO2 film as photoanode obtained a power conversion efficiency of 2.4%, which exceeded reported efficiency by 14%. Electrochemical impedance spectra (EIS) and Tafel-polarization measurements indicated that the enhanced performance was attributed to the superior catalytic activity and high diffusion coefficient at the interface between Co0.85Se CE and polysulfide electrolyte.

17.
J Med Virol ; 90(2): 204-211, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28892164

RESUMEN

The pattern recognition receptor retinoic acid-inducible gene I (RIG-I) reportedly plays a key role in sensing influenza A virus (IAV) infection and activating type I interferon (IFN) response. MCP-1-induced protein 1 (MCPIP1) can directly degrade cytokine mRNAs, such as IL-6, IL-12, IL-1ß, and IL-2, by functioning as an RNase. Here, we initially observed that MCPIP1 exhibited virus supportive functions later in the course of IAV infection in A549 cells, and negatively regulated IAV-induced RIG-I-dependent innate antiviral response. Exogenous overexpression of MCPIP1 suppressed the expression of RIG-I, whereas shRNA-mediated inhibition of endogenous MCPIP1 enhanced RIG-I expression. The results of experiments with actinomycin D and luciferase assay demonstrated that MCPIP1 reduced RIG-I expression through destabilizing its mRNA. Various mutants of functional domains of MCPIP1 further confirmed that the inhibitory effect of MCPIP1 on RIG-I expression required RNase activity but not deubiquitinase activity. Finally, the overexpression of several IAV proteins, which have the ability to inhibit the host IFN response at different levels, induced MCPIP1 expression, especially non-structural protein 1 (NS1). Conclusively, these data demonstrate the MCPIP1 contributes to attenuate IAV-induced host antiviral response by suppressing RIG-I expression.


Asunto(s)
Células Epiteliales/inmunología , Células Epiteliales/virología , Inmunidad Innata , Virus de la Influenza A/inmunología , Receptores de Ácido Retinoico/metabolismo , Ribonucleasas/metabolismo , Factores de Transcripción/metabolismo , Células A549 , Humanos , Pulmón/inmunología , Pulmón/virología
18.
Plant Cell Environ ; 41(10): 2449-2462, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29869796

RESUMEN

Cadmium (Cd) stress is one of the most serious heavy metal stresses limiting plant growth and development. However, the molecular mechanisms underlying Cd-induced root growth inhibition remain unclear. Here, we found that ethylene signalling positively regulates Cd-induced root growth inhibition. Arabidopsis seedlings pretreated with the ethylene precursor 1-aminocyclopropane-1-carboxylic acid exhibited enhanced Cd-induced root growth inhibition, whereas the addition of the ethylene biosynthesis inhibitor aminoethoxyvinyl glycine decreased Cd-induced root growth inhibition. Consistently, ethylene-insensitive mutants, such as ein4-1, ein3-1 eil1-1 double mutant, and EBF1ox, displayed an increased tolerance to Cd. Furthermore, we also observed that Cd inhibited EIN3 protein degradation, a process that was regulated by ethylene signalling. Genetic and biochemical analyses showed that EIN3 enhanced root growth inhibition under Cd stress through direct binding to the promoters and regulating the expression of XTH33 and LSU1, which encode key regulators of cell wall extension and sulfur metabolic process, respectively. Collectively, our study demonstrates that ethylene plays a positive role in Cd-regulated root growth inhibition through EIN3-mediated transcriptional regulation of XTH33 and LSU1 and provides a molecular framework for the integration of environmental signals and intrinsic regulators in modulating plant root growth.


Asunto(s)
Proteínas de Arabidopsis/fisiología , Arabidopsis/crecimiento & desarrollo , Cadmio/farmacología , Etilenos/metabolismo , Glicosiltransferasas/fisiología , Proteínas Nucleares/fisiología , Reguladores del Crecimiento de las Plantas/fisiología , Raíces de Plantas/crecimiento & desarrollo , Factores de Transcripción/fisiología , Arabidopsis/efectos de los fármacos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Unión al ADN , Ensayo de Cambio de Movilidad Electroforética , Regulación de la Expresión Génica de las Plantas , Glicosiltransferasas/metabolismo , Microscopía Confocal , Proteínas Nucleares/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/metabolismo , Plantas Modificadas Genéticamente , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores de Transcripción/metabolismo , Técnicas del Sistema de Dos Híbridos
19.
J Am Chem Soc ; 139(32): 10976-10979, 2017 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-28759209

RESUMEN

Preparing metal single-atom materials is currently attracting tremendous attention and remains a significant challenge. Herein, we report a novel core-shell strategy to synthesize single-atom materials. In this strategy, metal hydroxides or oxides are coated with polymers, followed by high-temperature pyrolysis and acid leaching, metal single atoms are anchored on the inner wall of hollow nitrogen-doped carbon (CN) materials. By changing metal precursors or polymers, we demonstrate the successful synthesis of different metal single atoms dispersed on CN materials (SA-M/CN, M = Fe, Co, Ni, Mn, FeCo, FeNi, etc.). Interestingly, the obtained SA-Fe/CN exhibits much higher catalytic activity for hydroxylation of benzene to phenol than Fe nanoparticles/CN (45% vs 5% benzene conversion). First-principle calculations further reveal that the high reactivity originates from the easier formation of activated oxygen species at the single Fe site. Our methodology provides a convenient route to prepare a variety of metal single-atom materials representing a new class of catalysts.

20.
Biochem Biophys Res Commun ; 482(4): 1107-1113, 2017 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-27914808

RESUMEN

The innate immune response provides the first line of defense against viruses and other pathogens by responding to specific microbial molecules. A20 is a cytoplasmic ubiquitin-editing protein that negatively regulates the retinoic acid-inducible gene I (RIG-I)-mediated activation of interferon regulatory factors (IRF) 3. Here, we found that influenza A virus (IAV) non-structural protein (NS) 1 dramatically induced the protein level of A20 in A549 cells whose expression levels were positively associated with the viral virulence. A20 overexpression in A549 cells significantly suppressed IAV-induced the activation of IRF3 and interferon (IFN) promoter, resulted in downregulation of IFNß and IFN-stimulated genes (ISGs) mRNA. Conversely, silencing A20 expression markedly enhanced IRF3-mediated innate antiviral responses. Furthermore, we demonstrated that A20 overexpression in A549 cells obviously promoted IAV replication, and conversely, knockdown of A20 inhibited the viral replication. Overall, the findings described in this study support and extend previous results on interferon-antagonistic strategies of IAV NS1 by showing an induced host target A20, which restricts IAV-induced host innate immune antiviral responses and thereby facilitates viral replication.


Asunto(s)
Inmunidad Innata , Virus de la Influenza A/fisiología , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfa/metabolismo , Proteínas no Estructurales Virales/metabolismo , Replicación Viral , Células A549 , Animales , Citoplasma/metabolismo , Perros , Silenciador del Gen , Humanos , Factor 3 Regulador del Interferón/metabolismo , Interferón beta/metabolismo , Células de Riñón Canino Madin Darby , ARN Mensajero/metabolismo , ARN Interferente Pequeño/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa
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