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1.
J Fluoresc ; 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38206512

RESUMO

An ethyl 3-aminobenzo[b]thiophene-2-carboxylate derived ratiometric Schiff base fluorescent sensor R was devised and synthesized. R exhibited a highly sensitive and selective ratiometric response to In3+ in DMF/H2O tris buffer solution. R exhibited a colorimetric/fluorescent dual-channel response to In3+. More importantly, R can distinguish In3+ from Ga3+ and Al3+ in less than 5 min. R exhibited a good linear correlation with the concentration of In3+ in the 5-25 µM range and the limit of detection for In3+ was found to be 8.36 × 10-9 M. According to the job`s plot and MS spectra, R formed a complex with In3+ at 1:2 with a complexation constant of 8.24 × 109 M2. Based on Gaussian theory calculations, the response mechanism of R to In3+ can be explained by photo-induced electron transfer (PET) and intramolecular charge transfer (ICT) mechanisms. In addition, R can be used for the detection of indium in tap water with satisfactory recoveries. Meanwhile, R displayed a linear relationship to micromolar concentrations (0-50 µM) of Pb2+ and recognized Pb2+ in a ratiometric response with a detection limit of 8.3 × 10-9 M.

2.
J Virol ; 96(12): e0016821, 2022 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-35638821

RESUMO

Positive-strand RNA viruses build large viral replication organelles (VROs) with the help of coopted host factors. Previous works on tomato bushy stunt virus (TBSV) showed that the p33 replication protein subverts the actin cytoskeleton by sequestering the actin depolymerization factor, cofilin, to reduce actin filament disassembly and stabilize the actin filaments. Then, TBSV utilizes the stable actin filaments as "trafficking highways" to deliver proviral host factors into the protective VROs. In this work, we show that the cellular intrinsic restriction factors (CIRFs) also use the actin network to reach VROs and inhibit viral replication. Disruption of the actin filaments by expression of the Legionella RavK protease inhibited the recruitment of plant CIRFs, including the CypA-like Roc1 and Roc2 cyclophilins, and the antiviral DDX17-like RH30 DEAD box helicase into VROs. Conversely, temperature-sensitive actin and cofilin mutant yeasts with stabilized actin filaments reduced the levels of copurified CIRFs, including cyclophilins Cpr1, CypA, Cyp40-like Cpr7, cochaperones Sgt2, the Hop-like Sti1, and the RH30 helicase in viral replicase preparations. Dependence of the recruitment of both proviral and antiviral host factors into VROs on the actin network suggests that there is a race going on between TBSV and its host to exploit the actin network and ultimately to gain the upper hand during infection. We propose that, in the highly susceptible plants, tombusviruses efficiently subvert the actin network for rapid delivery of proviral host factors into VROs and ultimately overcome host restriction factors via winning the recruitment race and overwhelming cellular defenses. IMPORTANCE Replication of positive-strand RNA viruses is affected by the recruitment of host components, which provide either proviral or antiviral functions during virus invasion of infected cells. The delivery of these host factors into the viral replication organelles (VROs), which represent the sites of viral RNA replication, depends on the cellular actin network. Using TBSV, we uncover a race between the virus and its host with the actin network as the central player. We find that in susceptible plants, tombusviruses exploit the actin network for rapid delivery of proviral host factors into VROs and ultimately overcome host restriction factors. In summary, this work demonstrates that the actin network plays a major role in determining the outcome of viral infections in plants.


Assuntos
Actinas , Fatores de Restrição Antivirais , Biogênese de Organelas , Tombusvirus , Replicação Viral , Fatores de Despolimerização de Actina/metabolismo , Actinas/metabolismo , Proteínas de Transporte/metabolismo , Ciclofilinas/metabolismo , Vírus de DNA/genética , RNA Viral/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/virologia , Proteínas de Saccharomyces cerevisiae , Tombusvirus/genética , Tombusvirus/fisiologia , Proteínas Virais/metabolismo
3.
Nano Lett ; 22(2): 740-750, 2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-35019663

RESUMO

Flexible transparent electrodes demand high transparency, low sheet resistance, as well as excellent mechanical flexibility simultaneously, however they still remain to be a great challenge due to"trade-off" effect. Herein, inspired by a hollow interconnected leaf vein, we developed robust transparent conductive mesh with biomimetic interwoven structure via hierarchically self-assembles silver nanowires interwoven metal carbide/nitride (MXene) sheets along directional microfibers. Strong interfacial interactions between plant fibers and conductive units facilitate hierarchically interwoven conductive mesh constructed orderly on flexible and lightweight veins while maintaining high transparency, effectively avoiding the trade-off effect between optoelectronic properties. The flexible transparent electrodes exhibit sheet resistance of 0.5 Ω sq-1 and transparency of 81.6%, with a remarkably high figure of merit of 3523. In addition, invisible camouflage sensors are further successfully developed as a proof of concept that could monitor human body motion signals in an imperceptible state. The flexible transparent conductive mesh holds great potential in high-performance wearable optoelectronics and camouflage electronics.


Assuntos
Nanofios , Biomimética , Eletrodos , Eletrônica , Humanos , Nanofios/química , Prata/química
4.
Langmuir ; 37(10): 3122-3129, 2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33682406

RESUMO

Most of the current sensors cannot meet the needs for seamless integration into the textile substrates of smart clothing and require improvements in terms of comfort and durability. Herein, smart textile-based sensors that have different sensing properties with integrated electronic elements were fabricated by knitting graphene-based helical conductive core-spun yarns. Such graphene-modified core-spun yarns are employed as building blocks of textile strain sensors, which showed high elasticity (ε > 300%), fast response time (120 ms), excellent reproducibility (over 10 000 cycles), wide sensing range (up to 100% strain), and low detection limit (0.3% strain). Thus, resistance-type strain sensors and capacitance-type pressure sensors composed of graphene-based smart fabric could be used to monitor large-scale limb movement and subtle human physiological signals. Such seamless smart textile-based fabric composed of superelastic helical conductive core-spun yarns shows great potential for fabricating an intelligent device to achieve real-time precise medicine and healthcare.

5.
Anal Chem ; 92(10): 7354-7362, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32319281

RESUMO

We propose a novel competitive mechanism involving the dissolved oxygen (O2) between zirconium-based porphyrinic metal-organic framework nanoparticles (NMOFs) and luminol into a ratiometric electrochemiluminescence (ECL) biosensing interface. Zinc tetrakis(carboxyphenyl)-porphyrin (ZnTCPP) in NMOFs as electron media reduce O2 into reactive oxygen species (ROS) and produce singlet oxygen (1O2), resulting in cathodic ECL. Meanwhile, ROS also react with the luminol anion radical and amplify the anodic ECL emission. Based on the competitive-mechanism-driven ECL process, taking the detection of polynucleotide kinase (PNK) as example, with assembling DNA-functionalized NMOFs on the sensing interface, a lower detection limit of 6.5 × 10-5 U mL-1 and broader linear relationship range from 0.0002 to 10 U mL-1 were obtained compared with that of single-signal-driven ECL sensors. This proposed MOFs-luminol competitive ECL mechanism involving dissolved O2 may provide a new pathway for further research of a green and highly sensitive ECL biosensing system.


Assuntos
Estruturas Metalorgânicas/química , Polinucleotídeo 5'-Hidroxiquinase/análise , Técnicas Biossensoriais , Técnicas Eletroquímicas , Inibidores Enzimáticos/farmacologia , Células HeLa , Humanos , Medições Luminescentes , Luminol , Estruturas Metalorgânicas/síntese química , Metaloporfirinas , Estrutura Molecular , Nanopartículas/química , Tamanho da Partícula , Polinucleotídeo 5'-Hidroxiquinase/antagonistas & inibidores , Polinucleotídeo 5'-Hidroxiquinase/metabolismo , Propriedades de Superfície , Zircônio
6.
PLoS Pathog ; 14(3): e1006894, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29513740

RESUMO

The E3 ubiquitin ligase COP1 (Constitutive Photomorphogenesis 1) is a well known component of the light-mediated plant development that acts as a repressor of photomorphogenesis. Here we show that COP1 positively regulates defense against turnip crinkle virus (TCV) and avrRPM1 bacteria by contributing to stability of resistance (R) protein HRT and RPM1, respectively. HRT and RPM1 levels and thereby pathogen resistance is significantly reduced in the cop1 mutant background. Notably, the levels of at least two double-stranded RNA binding (DRB) proteins DRB1 and DRB4 are reduced in the cop1 mutant background suggesting that COP1 affects HRT stability via its effect on the DRB proteins. Indeed, a mutation in either drb1 or drb4 resulted in degradation of HRT. In contrast to COP1, a multi-subunit E3 ligase encoded by anaphase-promoting complex (APC) 10 negatively regulates DRB4 and TCV resistance but had no effect on DRB1 levels. We propose that COP1-mediated positive regulation of HRT is dependent on a balance between COP1 and negative regulators that target DRB1 and DRB4.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/imunologia , Carmovirus/imunologia , Resistência à Doença/imunologia , Doenças das Plantas/imunologia , Proteínas de Ligação a RNA/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Arabidopsis/metabolismo , Arabidopsis/virologia , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Luz , Morfogênese , Mutação , Desenvolvimento Vegetal , Doenças das Plantas/virologia , Nicotiana/imunologia , Nicotiana/virologia , Ubiquitina-Proteína Ligases/genética
7.
Nano Lett ; 19(9): 6592-6599, 2019 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-31434486

RESUMO

Stretchable electrical conductors have demonstrated promising potentials in a wide range of wearable electronic devices, but the conductivity of most reported stretchable conductive fibers will be changed if be stretched or strained. Stable conductance is essential for wearable and stretchable devices, to ensure the performance is stable. Inspired by the peristaltic behavior of arthropods, we designed a graphene coating similar to the caterpillar structure on the polyurethane (PU) fiber surface, enabled by coating the worm-shaped graphene microlayer onto polyurethane filaments. Such worm-shaped filaments can be stretched up to 1010% with a wide reversible electroresponse range (0 < ε < 815%), long-term durability (>4000 stretching/releasing cycles), good initial conductivity (σ0 = 124 S m-1), and high quality factor (Q = 11.26). Remarkably, the worm-shaped filaments show distinctive strain-insensitive behavior (ΔR/R0 < 0.1) up to 220% strain. Furthermore, the filaments as electrical circuits of light emitting diodes (LEDs) to track signals from robust human joint movements are also demonstrated for practical application. Such worm-shaped filaments with distinctive strain-insensitive behavior provide a direct pathway for stretchy electronics.


Assuntos
Condutividade Elétrica , Grafite/química , Nanotubos de Carbono/química , Dispositivos Eletrônicos Vestíveis , Humanos
8.
J Exp Bot ; 70(5): 1627-1638, 2019 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-30843586

RESUMO

The Arabidopsis plasma membrane-localized resistance protein RPM1 is degraded upon the induction of the hypersensitive response (HR) triggered in response to its own activation or that of other unrelated resistance (R) proteins. We investigated the role of RPM1 turnover in RPM1-mediated resistance and showed that degradation of RPM1 is not associated with HR or resistance mediated by this R protein. Likewise, the runaway cell death phenotype in the lsd1 mutant was not associated with RPM1 degradation and did not alter RPM1-derived resistance. RPM1 stability and RPM1-mediated resistance were dependent on the double-stranded RNA binding (DRB) proteins 1 and 4. Interestingly, the function of DRB1 in RPM1-mediated resistance was not associated with its role in pre-miRNA processing. The DRB3 and DRB5 proteins negatively regulated RPM1-mediated resistance and a mutation in these completely or partially restored resistance in the drb1, drb2, and drb4 mutant backgrounds. Conversely, plants overexpressing DRB5 showed attenuated RPM1-mediated resistance. A similar role for DRBs in basal and R-mediated resistance suggests that these proteins play a general role in bacterial resistance.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Doenças das Plantas/genética , Pseudomonas syringae/fisiologia , Proteínas de Ligação a RNA/genética , Proteínas de Arabidopsis/metabolismo , Resistência à Doença/genética , Proteínas de Ligação a RNA/metabolismo
9.
Water Environ Res ; 89(6): 555-563, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-27095096

RESUMO

Water pollution is one of the most pervasive problems afflicting people. Therefore, seeking highly efficient, low-cost methods to decontaminate water is very much in demand. In this paper, chitosan/polyvinyl-alcohol composite sponges are synthesized via foamed cross-linking method while incorporating different amount of graphene oxide, the resultant graphene oxide/chitosan/polyvinyl-alcohol composite sponges (GCS) are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Fourier transform infrared (FTIR), indicating the reasonable dispersion of graphene oxide in the matrix. Furthermore, some physical properties (water absorption, water retention, apparent density, porosity) are also determined; water absorption is high up to 873%, apparent density is lower than 0.25 g/cm3, and porosity could reach 78%. The GCSs also manifest high adsorption ability, as effective adsorbent for Acid Red 37 (AR 37) solution. The relationship between adsorption capacity and independent variables (adsorbent mass, initial dye concentration, and contacting time) is obtained. The optimal adsorption capacity value of AR 37 on GCS could reach 421.5 mg/g.


Assuntos
Quitosana/química , Grafite/química , Álcool de Polivinil/química , Poluentes Químicos da Água/química , Adsorção , Corantes , Microscopia Eletrônica de Varredura , Eliminação de Resíduos Líquidos/métodos , Purificação da Água
10.
Water Environ Res ; 88(8): 768-78, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27456137

RESUMO

Graphene oxide has been used as an adsorbent in wastewater treatment. However, the hydrophily and dispersibility in aqueous solution limit its practical application in environmental protection. In this paper, a novel, environmentally friendly adsorbent, chitosan and chitosan-graphene oxide aerogels with a diverse shape, large specific surface area, and unique porous structure were prepared by a freeze-drying method. The structure of the adsorbents was investigated using scanning electron microscopy, Fourier transform-infrared spectroscopy, and X-ray diffraction (XRD); the specific surface area and swelling capability were also characterized. In addition, removal of diesel oil from seawater by chitosan aerogel (CSAG) and chitosan-graphene oxide aerogel (AGGO-1 and AGGO-2) was studied and batch adsorption experiments were carried out as a function of different adsorbent dosages (0-6 g), contact time (0-120 minutes), pH (3-9), and initial concentrations of oil residue (3-30 g/L) to determine the optimum condition for the adsorption of residue oil from seawater. The results showed that the chitosan-graphene oxide aerogels were more effective to remove diesel oil from seawater compared with pure chitosan aerogel. A removal efficiency ≥ 95% of the chitosan-graphene oxide aerogels could be achieved easily at the initial concentrations of 20 g/L, which indicated that the chitosan-graphene oxide aerogels can be used to treat the industrial oil leakage or effluent in the natural water.


Assuntos
Quitosana/química , Gasolina , Grafite/química , Água do Mar/análise , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Liofilização , Concentração de Íons de Hidrogênio , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Water Environ Res ; 88(7): 579-88, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27329054

RESUMO

Chitosan, modified with different dosages of graphene oxide (GO) and reduced graphene oxide (rGO), was first prepared, and its adsorption capacity for reactive red (RR) dye in aqueous solutions was investigated, in this paper. The structure and morphology of the adsorbents were characterized by FT-IR, XRD, SEM, EDX, BET, and TGA. The effect of varying parameters (pH, temperature, adsorbent loading, and contact time) was also investigated. The maximum adsorption capacity based on the Langmuir model was found to be 32.16 mg/g. In addition, experimental kinetic data were analyzed by the psuedo-first order and psuedo-second order equation models. The psuedo-second order model proved to be the best model for the adsorption system, which suggested that adsorption might be controlled by the chemical rate-limiting step through sharing of electrons or by covalent forces.


Assuntos
Quitosana/química , Corantes/química , Grafite/química , Eliminação de Resíduos Líquidos , Águas Residuárias/análise , Poluentes Químicos da Água/química , Adsorção , Óxidos/química
12.
Plant Cell ; 24(4): 1654-74, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22492810

RESUMO

The conserved cellular metabolites nitric oxide (NO) and oleic acid (18:1) are well-known regulators of disease physiologies in diverse organism. We show that NO production in plants is regulated via 18:1. Reduction in 18:1 levels, via a genetic mutation in the 18:1-synthesizing gene SUPPRESSOR OF SA INSENSITIVITY OF npr1-5 (SSI2) or exogenous application of glycerol, induced NO accumulation. Furthermore, both NO application and reduction in 18:1 induced the expression of similar sets of nuclear genes. The altered defense signaling in the ssi2 mutant was partially restored by a mutation in NITRIC OXIDE ASSOCIATED1 (NOA1) and completely restored by double mutations in NOA1 and either of the nitrate reductases. Biochemical studies showed that 18:1 physically bound NOA1, in turn leading to its degradation in a protease-dependent manner. In concurrence, overexpression of NOA1 did not promote NO-derived defense signaling in wild-type plants unless 18:1 levels were lowered. Subcellular localization showed that NOA1 and the 18:1 synthesizing SSI2 proteins were present in close proximity within the nucleoids of chloroplasts. Indeed, pathogen-induced or low-18:1-induced accumulation of NO was primarily detected in the chloroplasts and their nucleoids. Together, these data suggest that 18:1 levels regulate NO synthesis, and, thereby, NO-mediated signaling, by regulating NOA1 levels.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/imunologia , Arabidopsis/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/farmacologia , Ácido Oleico/metabolismo , Transdução de Sinais/efeitos dos fármacos , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Cloroplastos/efeitos dos fármacos , Cloroplastos/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Modelos Biológicos , Mutação/genética , Óxido Nítrico Sintase/genética , Fenótipo , Ligação Proteica/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos
13.
Pancreatology ; 15(4): 337-43, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26048200

RESUMO

BACKGROUND AND OBJECTIVES: Chinese herbal drug Da-Cheng-Qi decoction (DCQD) has been widely used for decades to treat acute pancreatitis (AP). Previous trials are mostly designed to state the potential mechanisms of the therapeutic effects rather than to detect its whole effect on metabolism. This study aimed to investigate the efficacy of DCQD on metabolism in AP. METHODS: Twenty-two male adult Sprague-Dawley rats were randomized into three groups. AP was induced by retrograde ductal infusion of 3.5% sodium taurocholate solution in DCQD and AP group, while 0.9% saline solution was used in sham operation (SO) group. Blood samples were obtained 12 h after drug administration and a 600 MHz superconducting Nuclear Magnetic Resonance (NMR) spectrometer was used to detected plasma metabolites. Principal Components Analysis (PCA) and Partial Least Squares-Discriminant Analysis after Orthogonal Signal Correction (OSC-PLS-DA) were applied to analyze the Longitudinal Eddy-delay (LED) and Carr-Purcell-Meiboom-Gill (CPMG) spectra. RESULTS: Differences in concentrations of metabolites among the three groups were detected by OSC-PLS-DA of 1HNMR spectra (both LED and CPMG). Compared with SO group, DCQD group had higher levels of plasma glycerol, glutamic acid, low density lipoprotein (LDL), saturated fatty acid (FA) and lower levels of alanine and glutamine, while the metabolic changes were reversed in the AP group. CONCLUSIONS: Our results demonstrated that DCQD was capable of altering the changed concentrations of metabolites in rats with AP and 1HNMR-based metabolomic approach provided a new methodological cue for systematically investigating the efficacies and mechanisms of DCQD in treating AP.


Assuntos
Medicamentos de Ervas Chinesas/farmacocinética , Medicamentos de Ervas Chinesas/uso terapêutico , Pancreatite/tratamento farmacológico , Pancreatite/metabolismo , Alanina/sangue , Animais , Biotransformação , LDL-Colesterol/sangue , Ácidos Graxos/sangue , Ácido Glutâmico/sangue , Glutamina/sangue , Glicerol/sangue , Espectroscopia de Ressonância Magnética , Masculino , Metabolômica , Ratos , Ratos Sprague-Dawley
14.
BMC Gastroenterol ; 14: 115, 2014 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-24975214

RESUMO

BACKGROUND: Acute pancreatitis (AP) is a common inflammatory disease of the pancreas accompanied by serious metabolic disturbances. Nevertheless, the specific metabolic process of this disease is still unclear. Characterization of the metabolome may help identify biomarkers for AP. To identify potential biomarkers, this study therefore investigated the 1H-nuclear magnetic resonance (NMR)-based metabolomic profile of AP. METHODS: Fourteen male adult Sprague-Dawley rats were randomized into two groups: the AP group, in which AP was induced by retrograde ductal infusion of 3.5% sodium taurocholate; and the sham operation group (SO), in which rats were infused with 0.9% saline. Blood samples were obtained 12 hours later and a 600 MHz superconducting NMR spectrometer was used to detect plasma metabolites. Principal components analysis (PCA) and partial least squares-discriminant analysis after orthogonal signal correction (OSC-PLS-DA) were used to analyze both longitudinal Eddy-delay (LED) and Carr-Purcell-Meiboom-Gill (CPMG) spectra. RESULTS: Differences in plasma metabolites between the two groups were detected by PCA and PLS-DA of 1HNMR spectra. Compared with the SO group, plasma levels of lactate (δ 1.3, 1.34, 4.1), valine (δ 0.98, 1.02), succinic acid (δ 2.38), 3-hydroxybutyric acid (3-HB, δ 1.18), high density lipoprotein (HDL, δ 0.8), and unsaturated fatty acid (UFA, δ 2.78, 5.3) were elevated in the AP group, while levels of glycerol (δ 3.58, 3.66), choline (δ 3.22), trimethylamine oxide (TMAO, δ 3.26), glucose (δ 3-4), glycine (δ 3.54), very low density lipoprotein (VLDL, δ 1.34) and phosphatidylcholine (Ptd, δ 2.78) were decreased. CONCLUSIONS: AP has a characteristic metabolic profile. Lactate, valine, succinic acid, 3-HB, HDL, UFA, glycerol, choline, TMAO, glucose, glycine, VLDL, and Ptd may be potential biomarkers of early stage AP.


Assuntos
Metaboloma , Pancreatite/sangue , Espectroscopia de Prótons por Ressonância Magnética , Animais , Colagogos e Coleréticos , Análise Discriminante , Análise dos Mínimos Quadrados , Masculino , Pancreatite/induzido quimicamente , Análise de Componente Principal , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Ácido Taurocólico
15.
J Phys Condens Matter ; 36(15)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38240186

RESUMO

We extend the highly-parallelizable open-source electronic transport code TRANSEC (Feldmanet al2014Phys. Rev.B90035445;https://gitlab.com/computational-physics2/transec/) to perform real-space atomic-scale electronic transport calculations with periodic boundary conditions in the lateral dimensions. We demonstrate the use of TRANSEC in periodic Cu and Rh bulk structures and in large periodic Rh point contacts, in preparation to perform calculations of reflection probability across Rh grain boundaries.

16.
J Hazard Mater ; 475: 134796, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38870851

RESUMO

Lead halide perovskite has demonstrated remarkable potential in the wearable field due to its exceptional photoelectric conversion capability. However, its lead toxicity issue has consistently been subject to criticism, significantly impeding its practical application. To address this challenge, an innovative approach called lead-rivet was proposed for the in-situ growth of perovskite crystalline structures. Through the formation of S-Pb bonds, each Pb2+ ion was firmly immobilized on the surface of the silica matrix, enabling in situ growth of perovskite nanocrystals via ion coordination between Cs+ and halide species. The robust S-Pb bonding effectively restricted the mobility of lead ions and stabilized the perovskite structure without relying on surface ligands, thereby not only preventing toxicity leakage but also providing a favorable interface for depositing protective shells. The obtained perovskites exhibit intense and narrow-band fluorescence with full-width at half-maximum less than 23 nm and show excellent stability to high temperature (above 202 °C) and high humidity (water immersion over 27 days), thus making it possible to be used in varies textile technologies including melt spinning and wet spinning. The lead leakage rate of particles is only 4.15 % demonstrating excellent toxicity inhibition performance. The prepared fibers maintained good extensibility and flexibility which could be used for 3D-printing and textiles weaving. Most importantly, the detected Pb2+ leaching was negligible as low as to 0.732 ppb which meet the standard of World Health Organization (WHO) for drinking water (<10 ppb), and the cell survival rate remained 99.196 % for PLA fluorescent filament after 24 h cultivation which showing excellent safety to human body and environment. This study establishes a controllable and highly adaptable synthesis method, thereby providing a promising avenue for the safe utilization of perovskite materials.


Assuntos
Compostos de Cálcio , Chumbo , Nanopartículas , Óxidos , Titânio , Óxidos/química , Óxidos/toxicidade , Compostos de Cálcio/química , Compostos de Cálcio/toxicidade , Chumbo/toxicidade , Chumbo/química , Titânio/química , Titânio/toxicidade , Nanopartículas/química , Nanopartículas/toxicidade , Humanos , Sobrevivência Celular/efeitos dos fármacos
17.
PLoS Pathog ; 7(11): e1002318, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22072959

RESUMO

EDS1, PAD4, and SAG101 are common regulators of plant immunity against many pathogens. EDS1 interacts with both PAD4 and SAG101 but direct interaction between PAD4 and SAG101 has not been detected, leading to the suggestion that the EDS1-PAD4 and EDS1-SAG101 complexes are distinct. We show that EDS1, PAD4, and SAG101 are present in a single complex in planta. While this complex is preferentially nuclear localized, it can be redirected to the cytoplasm in the presence of an extranuclear form of EDS1. PAD4 and SAG101 can in turn, regulate the subcellular localization of EDS1. We also show that the Arabidopsis genome encodes two functionally redundant isoforms of EDS1, either of which can form ternary complexes with PAD4 and SAG101. Simultaneous mutations in both EDS1 isoforms are essential to abrogate resistance (R) protein-mediated defense against turnip crinkle virus (TCV) as well as avrRps4 expressing Pseudomonas syringae. Interestingly, unlike its function as a PAD4 substitute in bacterial resistance, SAG101 is required for R-mediated resistance to TCV, thus implicating a role for the ternary complex in this defense response. However, only EDS1 is required for HRT-mediated HR to TCV, while only PAD4 is required for SA-dependent induction of HRT. Together, these results suggest that EDS1, PAD4 and SAG101 also perform independent functions in HRT-mediated resistance.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/virologia , Hidrolases de Éster Carboxílico/metabolismo , Carmovirus/imunologia , Proteínas de Ligação a DNA/metabolismo , Doenças das Plantas/imunologia , Imunidade Vegetal , Sequência de Aminoácidos , Arabidopsis/imunologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/biossíntese , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/imunologia , Proteínas de Bactérias , Hidrolases de Éster Carboxílico/biossíntese , Hidrolases de Éster Carboxílico/genética , Núcleo Celular/metabolismo , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/virologia , Proteínas de Plantas/biossíntese , Ligação Proteica , Isoformas de Proteínas/biossíntese , Isoformas de Proteínas/genética , Estrutura Quaternária de Proteína , Proteínas Repressoras/metabolismo , Alinhamento de Sequência , Transdução de Sinais
18.
PLoS Genet ; 5(7): e1000545, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19578402

RESUMO

Resistance (R) protein-associated pathways are well known to participate in defense against a variety of microbial pathogens. Salicylic acid (SA) and its associated proteinaceous signaling components, including enhanced disease susceptibility 1 (EDS1), non-race-specific disease resistance 1 (NDR1), phytoalexin deficient 4 (PAD4), senescence associated gene 101 (SAG101), and EDS5, have been identified as components of resistance derived from many R proteins. Here, we show that EDS1 and SA fulfill redundant functions in defense signaling mediated by R proteins, which were thought to function independent of EDS1 and/or SA. Simultaneous mutations in EDS1 and the SA-synthesizing enzyme SID2 compromised hypersensitive response and/or resistance mediated by R proteins that contain coiled coil domains at their N-terminal ends. Furthermore, the expression of R genes and the associated defense signaling induced in response to a reduction in the level of oleic acid were also suppressed by compromising SA biosynthesis in the eds1 mutant background. The functional redundancy with SA was specific to EDS1. Results presented here redefine our understanding of the roles of EDS1 and SA in plant defense.


Assuntos
Proteínas de Arabidopsis/imunologia , Arabidopsis/imunologia , Proteínas de Ligação a DNA/imunologia , Imunidade Inata , Doenças das Plantas/imunologia , Ácido Salicílico/imunologia , Ácido Salicílico/metabolismo , Transdução de Sinais , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/virologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Carmovirus/fisiologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica de Plantas , Transferases Intramoleculares/genética , Transferases Intramoleculares/metabolismo , Doenças das Plantas/virologia
19.
Biomed Pharmacother ; 146: 112587, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35062061

RESUMO

Chronic alcohol consumption, which is observed worldwide, can damage pancreatic tissue and promote pancreatitis. Rhubarb is a widely used traditional Chinese herbal medicine for treating pancreatitis in China. However, few pharmacological studies have investigated its epigenetic regulation. In this study, we investigated whether chronic exposure to alcohol can alter inflammatory gene expression and the epigenetic regulation effect of cooked rhubarb in the pancreatic tissue of rats. First, changes in inflammatory cytokine DNA methylation (IL-10, IL-1α, TNF-α, NF-κB and TGF-ß) were detected in pancreatic tissue of Sprague-Dawley rats with varying alcohol exposure times (4, 6, 8, or 12 weeks), and then with varying doses of cooked rhubarb treatment (3, 6, or 12 g/day). DNA methylation levels, related RNA concentrations and protein expression of specific inflammatory cytokines, and histopathological score were analysed in pancreatic tissue of Sprague-Dawley rats. The results showed that chronic alcohol exposure (8 weeks) reduced the level of IL-1α DNA methylation and increased its protein expression in acinar cells (P < 0.05). In the acinar cells, the level of IL-10 DNA methylation increased, resulting in a reduction of protein expression (P < 0.05). Simultaneously, chronic alcohol exposure increased the pathological damage to the pancreas (P < 0.05). Finally, cooked rhubarb treatment (3 g/kg/day) effectively alleviated these changes in pancreatic tissue from chronic alcohol exposure (P < 0.05). These results indicate that chronic exposure to alcohol leads to changes in DNA methylation and protein expression of inflammatory genes, and cooked rhubarb may have a protective effect on the pancreatic tissue of rats.


Assuntos
Epigênese Genética , Etanol/metabolismo , Medicina Tradicional Chinesa , Pâncreas/patologia , Rheum , Animais , China , Metilação de DNA/efeitos dos fármacos , Humanos , Interleucina-10/metabolismo , Interleucina-1alfa/metabolismo , Masculino , Pâncreas/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo
20.
ACS Appl Mater Interfaces ; 13(47): 56607-56619, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34786929

RESUMO

Wearable electronics have enriched daily lives by providing smart functions as well as monitoring body health conditions. However, the realization of wearable electronics with personal healthcare and thermal comfort management of the human body is still a great challenge. Furthermore, manufacturing such on-skin wearable electronics on traditional thin-film substrates results in limited gas permeability and inflammation. Herein, we proposed a personal healthcare and thermal management smart textile with a three-dimensional (3D) interconnected conductive network, formed by silver nanowires (AgNWs) bridging lamellar structured transition-metal carbide/carbonitride (MXene) nanosheets deposited on nonwoven fabrics. Benefiting from the interconnected conductive network synergistic effect of one-dimensional (1D) AgNWs bridging two-dimensional (2D) MXene, the strain sensor exhibits excellent durability (>1500 stretching cycles) and high sensitivity (gauge factor (GF) = 1085) with a wide strain range limit (∼100%), and the details of human body activities can be accurately recognized and monitored. Moreover, thanks to the excellent Joule heating and photothermal effect endowed by AgNWs and MXene, the multifunctional smart textile with direct temperature visualization and solar-powered temperature regulation functions was successfully developed, after further combination of thermochromic and phase-change functional layers, respectively. The smart textiles with a stretchable AgNW-MXene 3D conductive network hold great promise for next-generation personal healthcare and thermal management wearable systems.


Assuntos
Atenção à Saúde , Pessoal de Saúde , Monitorização Fisiológica , Nanofios/química , Prata/química , Dispositivos Eletrônicos Vestíveis , Condutividade Elétrica , Humanos , Monitorização Fisiológica/instrumentação , Tamanho da Partícula , Propriedades de Superfície , Temperatura , Têxteis
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