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1.
Nat Genet ; 56(2): 315-326, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38238629

RESUMO

Gray leaf spot (GLS), caused by the fungal pathogens Cercospora zeae-maydis and Cercospora zeina, is a major foliar disease of maize worldwide (Zea mays L.). Here we demonstrate that ZmWAKL encoding cell-wall-associated receptor kinase-like protein is the causative gene at the major quantitative disease resistance locus against GLS. The ZmWAKLY protein, encoded by the resistance allele, can self-associate and interact with a leucine-rich repeat immune-related kinase ZmWIK on the plasma membrane. The ZmWAKLY/ZmWIK receptor complex interacts with and phosphorylates the receptor-like cytoplasmic kinase (RLCK) ZmBLK1, which in turn phosphorylates its downstream NADPH oxidase ZmRBOH4. Upon pathogen infection, ZmWAKLY phosphorylation activity is transiently increased, initiating immune signaling from ZmWAKLY, ZmWIK, ZmBLK1 to ZmRBOH4, ultimately triggering a reactive oxygen species burst. Our study thus uncovers the role of the maize ZmWAKL-ZmWIK-ZmBLK1-ZmRBOH4 receptor/signaling/executor module in perceiving the pathogen invasion, transducing immune signals, activating defense responses and conferring increased resistance to GLS.


Assuntos
Locos de Características Quantitativas , Zea mays , Zea mays/genética , Zea mays/microbiologia , Doenças das Plantas/microbiologia , Resistência à Doença/genética
2.
J Hazard Mater ; 421: 126722, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34332480

RESUMO

The novel sulfomethylated lignin-grafted-polyacrylic acid (SL-g-PAA) hydrogel was fabricated in this work via a facile and green synthetic strategy for the efficient removal of heavy metal ions from wastewater, and then successively reused for chemiluminescence (CL). The sulfomethylation of lignin was first performed to improve its water solubility and introduce numerous active sites for adsorption of heavy metal ions. The as-synthesized SL-g-PAA hydrogel with high content of lignin exhibited the highly efficient and rapid removal of various metal ions from simulated wastewater. More importantly, the spent hydrogel (M2+@SL-g-PAA) after adsorption was reused for the first time to develop a new CL system by an ingenious strategy, in which these metal ions adsorbed on M2+@SL-g-PAA act as heterogeneous catalytic sites to catalyze the CL reaction between N-(4-aminobutyl)-N-ethylisoluminol (ABEI) and H2O2. The resultant CL system displayed high CL intensity and long duration time, which could be observed by naked eye in the dark and lasted for > 24 h. The combination of facile fabrication process, renewable raw materials, and ingenious strategy for successive application in adsorption and CL endows this lignin-based composite hydrogel with a great potential for application in wastewater treatment, biological imaging and cold light sources.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Adsorção , Hidrogéis , Peróxido de Hidrogênio , Íons , Lignina , Luminescência , Águas Residuárias , Poluentes Químicos da Água/análise
3.
ChemSusChem ; 14(22): 4903-4922, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34636483

RESUMO

Photoreforming of biomass into hydrogen, biofuels, and chemicals is highly desired, yet this field of research is still in its infancy. Developing an efficient, novel, and environmentally friendly photocatalyst is key to achieving these goals. To date, the nonmetallic and eco-friendly material carbon nitride has found many uses in reactions such as water splitting, CO2 reduction, N2 fixation, and biorefinery, owing to its outstanding photocatalytic activity. However, a narrow light absorption range and fast charge recombination are often encountered in the pristine carbon nitride photocatalytic system, which resulted in unsatisfying photocatalytic activity. To improve the photocatalytic performance of pure carbon nitride in biomass reforming, modification is needed. In this Review, the design and preparation of functional carbon nitride, as well as its photocatalytic properties for the synthesis of hydrogen, biofuels, and chemicals through biomass reforming, are discussed alongside potential avenues for its future development.

4.
Int J Biol Macromol ; 182: 1484-1494, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34019923

RESUMO

Development of lignin-derived carbon adsorbents with ultrahigh phosphate adsorption activity and rapid adsorption kinetics is of great importance, yet limited success has been achieved. Herein, we develop a CeO2 functionalized N-doped lignin-derived biochar (Ce@NLC) via a cooperative modification strategy for effective and fast phosphate capture. The novel modification strategy not only contributes greatly to the loading of well-dispersed CeO2 nanoparticles with a smaller size, but also significantly increases the relative concentration of Ce(III) species on Ce@NLC. Consequently, an enhanced capture capacity for phosphate (196.85 mg g-1) as well as extremely rapid adsorption kinetics were achieved in a wide operating pH range (2-10). Interestingly, Ce@NLC exhibited a strong phosphate adsorption activity at even low-concentration phosphorus-containing water. The removal efficiency and final P concentration reached 99.87% and 2.59 µg P L-1 within 1 min at the phosphate concentration of 2 mg P L-1. Experiments and characterization indicated that Ce(III) species plays a predominant role for the phosphate capture, and ligand exchange, together with electrostatic attraction, are the main adsorption mechanism. This work develops not only an efficient carbon-based adsorbent for phosphate capture, but also promotes the high-value application of industrial lignin.


Assuntos
Cério/química , Lignina/química , Nanopartículas Metálicas/química , Nitrogênio/química , Fosfatos/química
5.
Chemosphere ; 278: 130377, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33819886

RESUMO

As the severe damage of phosphate enrichment in the water ecosystem and the supply shortage of phosphate rock, developing an efficient method for the removal and recycling of phosphate from wastewater is of great significance. To achieve this goal, adsorption technology has been widely investigated, and various adsorbents were developed. Among them, the biomass-derived adsorbents including biomass-derived carbon-based materials, biomass-based anion exchangers and metal-biomass composites have attracted increasing attention over the past years due to the low cost, abundant renewable raw materials and environmental friendliness. However, different adsorbents usually exhibit variable adsorption performances for phosphate, which highly depends on their design strategies, preparation methods and potential adsorption mechanisms. Thus, this review comprehensively summarizes the recent researches on the removal and recycling of phosphate from wastewater using the biomass-derived adsorbents. Especially, the design strategies, preparation methods, adsorption performances and mechanisms of these reported biomass-derived adsorbents are discussed in detail. Moreover, as the significant strategies to recover and recycling phosphate, the elution and direct use of phosphate-loaded adsorbents as fertilizers are also presented. Although the excellent adsorption performance has been obtained, some challenges are still existing, which should be given more attention in the following researches to facilitate the development and industrial application of biomass-derived adsorbents.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Biomassa , Ecossistema , Fosfatos , Águas Residuárias
6.
Sci Total Environ ; 761: 143217, 2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33162139

RESUMO

Design of carbon-based adsorbents derived from industrial lignin with superior phosphate adsorption performance is of great significance, yet limited researches have been reported. Here, we report a MgO-functionalized lignin-based bio-charcoal (MFLC) as an efficient adsorbent for phosphate removal. The obtained MgO nanoparticles were dispersed homogeneously on MFLC with particle size of 50-100 nm and higher loading content (28.41%). Benefiting from the favorable morphology of MgO nanoparticles, the MFLC exhibits excellent regeneration ability for phosphate adsorption, which can be applied in a wide range of pH values (2-10). The maximum adsorption capacity could reach to 906.82 mg g-1 for phosphate. Interestingly, the MFLC shows extremely high adsorption activity in the low concentration of phosphate (2 mg P L-1), and its phosphate removal efficiency achieves 99.76%. Furthermore, the results also indicated that the higher loading content of MgO together with smaller particle size can effectively enhance the phosphate adsorption activity of MFLC. The adsorption mechanism revealed that the adsorption of phosphate on the surface of MFLC belongs to single-layer chemisorption, and ligand exchange plays a crucial role during adsorption/desorption. This work not only develops a new strategy for the preparation of high-efficiency carbon-based adsorbents, but also facilitates the value-added utilization of industrial lignin.


Assuntos
Fosfatos , Poluentes Químicos da Água , Adsorção , Carbono , Carvão Vegetal , Cinética , Lignina , Poluentes Químicos da Água/análise
7.
Cancer Lett ; 344(2): 239-59, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24280585

RESUMO

Plumbagin (PLB) has shown anti-cancer activity but the mechanism is unclear. This study has found that PLB has a potent pro-apoptotic and pro-autophagic effect on A549 and H23 cells. PLB arrests cells in G2/M phase, and increases the intracellular level of reactive oxygen species in both cell lines. PLB dose-dependently induces autophagy through inhibition of PI3K/Akt/mTOR pathway as indicated by reduced phosphorylation of Akt and mTOR. Inhibition or induction of autophagy enhances PLB-induced apoptosis. There is crosstalk between PLB-induced apoptosis and autophagy. These findings indicate that PLB initiates both apoptosis and autophagy in NSCLC cells through coordinated pathways.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Naftoquinonas/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Serina-Treonina Quinases TOR/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Humanos , Neoplasias Pulmonares/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo
8.
Ann Surg Oncol ; 20(7): 2266-73, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23370668

RESUMO

BACKGROUND: Papillary thyroid carcinoma (PTC) is one of the most common endocrine malignancies. It is estimated that papillary thyroid microcarcinoma (PTMC) accounts for up to 30 % of all PTCs. The clinical significance of PTMC is still unclear, although it may be related to recurrence, distant metastasis, and mortality. The purpose of this study was to analyze the clinical characteristics and BRAF(V600E) mutational status of PTMCs in a Chinese population and to determine risk factors for poor prognosis. METHODS: We performed a retrospective review of 977 PTMC cases that underwent surgical resection from January 2001 to January 2010 at Tianjin Medical University Cancer Institute and Hospital. RESULTS: The mean size of 977 PTMCs was 5.2 (range, 2-10) mm. Multifocal tumors were seen in 323 patients. The majority of patients (692) had a T1 lesion, whereas 279 had T3 and 6 had T4a; 40.1 % patients had BRAF(V600E) mutation. The frequencies of extrathyroidal extension and lymph node metastasis were 29.2 and 23.4 %, respectively. Distant metastasis was present in 15 patients. Half of the patients (50.8 %) received a total thyroidectomy and others had a lobectomy. CONCLUSIONS: The present study suggests that highly aggressive PTMCs may arise in a subset of patients with BRAF(V600E) mutation and tumors greater than 5 mm. Extrathyroidal invasion, lymph node metastases, and the type of surgical procedures were significantly associated with tumor recurrence. Although multivariate analysis showed that tumor recurrence was not associated with BRAF(V600E) mutation, it has not been shown that treating these patients more aggressively changes outcomes.


Assuntos
Carcinoma/genética , Carcinoma/patologia , Mutação , Neoplasias Primárias Múltiplas/genética , Neoplasias Primárias Múltiplas/patologia , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Adulto , Idoso , Povo Asiático/genética , Carcinoma/cirurgia , Carcinoma Papilar , China , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Neoplasias Primárias Múltiplas/cirurgia , Prognóstico , Recidiva , Estudos Retrospectivos , Fatores de Risco , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia , Adulto Jovem
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