Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
BMC Plant Biol ; 24(1): 318, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38654190

RESUMO

BACKGROUND: Class III peroxidases (PODs) perform crucial functions in various developmental processes and responses to biotic and abiotic stresses. However, their roles in wheat seed dormancy (SD) and germination remain elusive. RESULTS: Here, we identified a wheat class III POD gene, named TaPer12-3A, based on transcriptome data and expression analysis. TaPer12-3A showed decreasing and increasing expression trends with SD acquisition and release, respectively. It was highly expressed in wheat seeds and localized in the endoplasmic reticulum and cytoplasm. Germination tests were performed using the transgenic Arabidopsis and rice lines as well as wheat mutant mutagenized with ethyl methane sulfonate (EMS) in Jing 411 (J411) background. These results indicated that TaPer12-3A negatively regulated SD and positively mediated germination. Further studies showed that TaPer12-3A maintained H2O2 homeostasis by scavenging excess H2O2 and participated in the biosynthesis and catabolism pathways of gibberellic acid and abscisic acid to regulate SD and germination. CONCLUSION: These findings not only provide new insights for future functional analysis of TaPer12-3A in regulating wheat SD and germination but also provide a target gene for breeding wheat varieties with high pre-harvest sprouting resistance by gene editing technology.


Assuntos
Germinação , Dormência de Plantas , Triticum , Triticum/genética , Triticum/enzimologia , Triticum/fisiologia , Dormência de Plantas/genética , Germinação/genética , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/fisiologia , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Peróxido de Hidrogênio/metabolismo , Giberelinas/metabolismo , Arabidopsis/genética , Arabidopsis/fisiologia , Peroxidases/genética , Peroxidases/metabolismo , Plantas Geneticamente Modificadas , Ácido Abscísico/metabolismo , Genes de Plantas
2.
Clin Nutr ; 43(6): 1372-1383, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38678822

RESUMO

BACKGROUND & AIMS: Sepsis-induced disseminated intravascular coagulation (DIC) is characterised by abnormal blood clotting resulting from severe infection, contributing to organ dysfunction in sepsis. Resolvin D1 (RvD1) is an endogenous lipid mediator, synthesised from the omega-3 polyunsaturated fatty acid (PUFA) docosahexaenoic acid (DHA) through enzymatic processes involving 15-LOX and 5-LOX. RvD1 is recognised for its protective properties against various inflammatory conditions. This study aims to investigate its potential to modulate coagulation dysfunction in sepsis and to evaluate coagulation disorders in septic patients. METHODS: Sepsis models were established by intraperitoneal injection LPS (20 mg/kg) or cecal ligation and puncture (CLP) followed by injection of RvD1 (10 µg/kg) or saline. The impact of RvD1 on coagulation dysfunction was assessed by clotting time and coagulation indicators such as TAT, D-dimer, PAI-1, and fibrinogen. The activity of the coagulation system in vivo was observed by evaluating dynamic microcirculation, platelets and thrombin in mice using intravital microscopy. The effect of RvD1 on pyroptosis was investigated by measuring NOD-like receptor protein 3 (NLRP3), Caspase-1, Caspase-11, and Gasdermin D (GSDMD) levels via western blot. Caspase-1 knockout mice, GSDMD knockout mice and bone marrow-derived macrophages (BMDMs) were used to elucidate the underlying mechanisms. Lastly, the concentration of RvD1 in plasma from septic patients was quantified to explore its relationship with coagulation and pyroptosis. RESULTS: RvD1 significantly attenuated coagulation dysfunction in septic mice induced by LPS and CLP, and inhibited Caspase-1/GSDMD-dependent pyroptosis in septic mice and bone marrow-derived macrophages. In septic patients, the plasma concentrations of RvD1 was negatively correlated with both coagulation-related indicators and markers of GSDMD activation. CONCLUSION: The results suggest that RvD1 can improve coagulation dysfunction in sepsis by regulating the Caspase-1/GSDMD pyroptotic pathway. Additionally, the concentration of RvD1 in septic patient plasma is related to prognosis and DIC development. RvD1 could be a potential biomarker and a promising therapeutic alternative in sepsis-induced DIC.

3.
Environ Res ; 243: 117668, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38007082

RESUMO

In recent years, one of the most important and innovative policy initiatives introduced by the Chinese government in the field of environmental protection and ecological civilization construction is the Central Environmental Protection Inspection (CEPI). CEPI is seen as a vital tool to encourage local implementation of environmental protection responsibility. Over the course of its operation (eight years), CEPI has transformed from the "campaign" phase to the "convention" phase. It is noted that while provincial governments face a common high-pressure environment created by CEPI, governance scenarios, behaviors, and performance vary across the country significantly. To better understand local governments' environmental governance behaviors under the transformation of CEPI, an integrated analysis framework consisting of two key elements, "central dominance" and "local proactiveness", is constructed based on the central-local interactions under the principal-agent model. Based on this framework, we conducted a multi-case comparative analysis of four classic cases, with the following findings. (1) Along with the operation of CEPI and its transformation, the interaction between the central and local governments leads to four governance scenarios: "control-active cooperation", "control-passive cooperation", "guidance-active promotion", and "guidance-passive promotion". (2) Influenced by various factors such as pressure by the central government, local governments' capabilities and governance motivations, local governments form governance behaviors with varying degrees of proactiveness and autonomy. (3) After examining the governance performance of varying behaviors, it is found that local government's "active promotion" behavior can achieve higher governance effectiveness in the "convention" phase. Therefore, it is of policy implication that local governments should be guided to transit from "passive cooperation" to "active promotion". This paper has important guiding significance for understanding local environmental governance behaviors under strong top-down institutional pressure.


Assuntos
Conservação dos Recursos Naturais , Política Ambiental , China , Governo
4.
Front Plant Sci ; 14: 1107277, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36818881

RESUMO

Introduction: Seed dormancy (SD) significantly decreases under high temperature (HT) environment during seed maturation, resulting in pre-harvest sprouting (PHS) damage under prolonged rainfall and wet weather during wheat harvest. However, the molecular mechanism underlying HT-mediated SD remains elusiveSeed dormancy (SD) significantly decreases under high temperature (HT) environment during seed maturation, resulting in pre-harvest sprouting (PHS) damage under prolonged rainfall and wet weather during wheat harvest. However, the molecular mechanism underlying HT-mediated SD remains elusive. Methods: Here, the wheat landrace 'Waitoubai' with strong SD and PHS resistance was treated with HT from 21 to 35 days post anthesis (DPA). Then, the seeds under HT and normal temperature (NT) environments were collected at 21 DPA, 28 DPA, and 35 DPA and subjected to whole-transcriptome sequencing. Results: The phenotypic data showed that the seed germination percentage significantly increased, whereas SD decreased after HT treatment compared with NT, consistent with the results of previous studies. In total, 5128 mRNAs, 136 microRNAs (miRNAs), 273 long non-coding RNAs (lncRNAs), and 21 circularRNAs were found to be responsive to HT, and some of them were further verified through qRT-PCR. In particular, the known gibberellin (GA) biosynthesis gene TaGA20ox1 (TraesCS3D02G393900) was proved to be involved in HT-mediated dormancy by using the EMS-mutagenized wheat cultivar Jimai 22. Similarly, a novel gene TaCDPK21 (TraesCS7A02G267000) involved in the calcium signaling pathway was validated to be associated with HT-mediated dormancy by using the EMS mutant. Moreover, TaCDPK21 overexpression in Arabidopsis and functional complementarity tests supported the negative role of TaCDPK21 in SD. We also constructed a co-expression regulatory network based on differentially expressed mRNAs, miRNAs, and lncRNAs and found that a novel miR27319 was located at a key node of this regulatory network. Subsequently, using Arabidopsis and rice lines overexpressing miR27319 precursor or lacking miR27319 expression, we validated the positive role of miR27319 in SD and further preliminarily dissected the molecular mechanism of miR27319 underlying SD regulation through phytohormone abscisic acid and GA biosynthesis, catabolism, and signaling pathways. Discussion: These findings not only broaden our understanding of the complex regulatory network of HT-mediated dormancy but also provide new gene resources for improving wheat PHS resistance to minimize PHS damage by using the molecular pyramiding approach.

5.
Sci Total Environ ; 831: 154743, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35337879

RESUMO

The enrichment and recovery of U(VI) from low-level radioactive wastewater in the process of uranium enrichment is important for the sustainable development of nuclear energy and environmental protection. Herein, a novel amine-aminophosphonate bifunctionalized polyacrylonitrile fiber (AAP-PAN), was prepared for the extraction of U(VI) from simulated and real uranium-containing process wastewater. The AAP-PAN fiber demonstrated a maximum adsorption capacity of 313.6 mg g-1 at pH = 6.0 and 318 K in the batch experiments. During the dynamic column experiment, over 99.99% removal of U(VI) could be achieved by the fiber using multi-ion simulated solution and real wastewater with an excellent saturation adsorption capacity of 132.0 mg g-1 and 72.5 mg g-1, respectively. It also exhibited an outstanding reusability for at least 5 cycles of adsorption process. The mechanism for U(VI) removal was studied by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy analysis in the assist of simulation calculation. It suggested that the amine and aminophosphonate groups can easily bind uranyl ions due to U(VI) is more likely to combine with oxygen atoms of CO and PO, respectively.


Assuntos
Urânio , Resinas Acrílicas , Adsorção , Aminas , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Urânio/análise , Águas Residuárias/análise
6.
J Hazard Mater ; 424(Pt C): 127542, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34740162

RESUMO

Chromium (Cr), especially in forms of hexavalent chromium (Cr(VI)) remains a serious threat to public health and environmental safety for its high toxicity. Herein, two types of iron-modification methods adopting co-pyrolysis and surface-deposition respectively were carried out to prepare active Fe-biochar composites (FeBC) for Cr(VI) removal in the simulated groundwater environment. The systematic characterization demonstrated that larger BET surface area and diversified iron oxides of FeBC-1 obtained from the co-pyrolysis method contributed to higher adsorption and reduction activity towards Cr(VI) degradation in comparison with FeBC-2 produced from surface-deposition method. Further, FeO was evidenced to be a main active component for transforming Cr(VI) to lower-toxicity Cr(III) uniting XRD and XPS analysis. Also, the designed batch experiments aiming at deeper clarifying FeBC-1 revealed that the pseudo-second-order kinetic and intra-particle diffusion model could well describe the Cr(VI) sorption behaviors, suggesting that a single-layer, chemical adsorption process as well as internal particle diffusion both controlled the removal process of Cr(VI) using FeBC-1. Finally, the stability experiments stated that FeBC-1 was basically stable at acidic and neutral conditions. Thus, it was found that co-pyrolysis of FeBC-1 is a potential technology for Cr(VI) remediation.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Cromo/análise , Elétrons , Ferro , Cinética , Óxidos , Poluentes Químicos da Água/análise
7.
Chemosphere ; 286(Pt 2): 131721, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34352550

RESUMO

The discharge of chromium (Cr) contaminated wastewater is creating a serious threat to aquatic environment due to the rapid pace in agricultural and industrial activities. Particularly, the long-term exposure of Cr(VI) polluted wastewater to the environment is causing serious harm to human health. Therefore, the treatment of Cr(VI) contaminated wastewater is demanding widespread attention. Regarding this, the bioremediation is being considered as a reliable and feasible option to handle Cr(VI) contaminated wastewater because of having low technical investment and operating costs. However, certain factors such as loss of microorganisms, toxicity to microorganisms and uneven microbial growth cycle in the presence of high concentrations of Cr(VI) are hindering its commercial applications. Regarding this, microbial immobilization technology (MIT) is getting great research interest because it could overcome the shortcomings of bioremediation technology's poor tolerance against Cr. Therefore, this review is the first attempt to emphases recent research developments in the remediation of Cr(VI) contamination via MIT. Starting from the selection of immobilized carrier, the present review is designed to critically discuss the various microbial immobilizing methods i.e., adsorption, embedding, covalent binding and medium interception. Further, the mechanism of Cr(VI) removal by immobilized microorganism has also been explored, precisely. In addition, three kinds of microorganism immobilization devices have been critically examined. Finally, knowledge gaps/key challenges and future perspectives are also discussed that would be helpful for the experts in improving MIT for the remediation of Cr(VI) contamination.


Assuntos
Cromo , Águas Residuárias , Biodegradação Ambiental , Cromo/análise , Humanos , Tecnologia
8.
Methods ; 202: 117-126, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34274447

RESUMO

Epilepsy is a neurological disorder that affects approximately 1% of the world's populations. Epilepsy prediction has been of great interest as it can identify and warn of an upcoming seizure, and to reduce the burden of the unpredictability of seizures. In this paper, we proposed a new seizure prediction model, TASM_ResNet, based on a time-wise attention simulation module and a pre-trained ResNet, using intracranial EEG signals. The simulation module with a time-wise attention was designed to convert EEG data into image like data and extract temporal features from raw data. Pre-trained ResNet was applied to reduce the amount of training data without initial training. Moreover, since the data is extremely imbalanced, we used an improved focal loss (FL) instead of the cross-entropy loss and investigated the optimal parameters for FL. Compared with a state-of-art CNN model, our proposed model achieved a better average AUC of 0.877. Moreover, our results demonstrated that EEG signals can be migrated to the image network which was pre-trained on large data set through a simulation module.


Assuntos
Eletroencefalografia , Epilepsia , Algoritmos , Atenção , Eletroencefalografia/métodos , Epilepsia/diagnóstico , Humanos , Convulsões/diagnóstico
9.
Plant Physiol Biochem ; 169: 343-359, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34837867

RESUMO

GATA transcription factors have been reported to function in plant growth and development and during various biotic/abiotic stresses in Arabidopsis and rice. However, the functions of wheat GATAs, particularly in the regulation of seed dormancy and germination, remain unclear. Here, we identified 78 TaGATAs in wheat and divided them into five subfamilies. Sixty-four paralogous pairs and 52 orthologous pairs were obtained, and Ka/Ks ratios showed that the TaGATAs had undergone strong purifying election during the evolutionary process. Triplet analysis indicated that a high homologue retention rate could explain the large number of TaGATAs in wheat. Gene structure analysis revealed that most members of the same subfamily had similar structures, and subcellular localization prediction indicated that most TaGATAs were located in the nucleus. Gene ontology annotation results showed that most TaGATAs had molecular functions in DNA and zinc binding, and promoter analysis suggested that they may play important roles in growth, development, and biotic/abiotic stress response. We combined three microarray datasets with qRT-PCR expression data from wheat varieties of contrasting dormancy and pre-harvest sprouting resistance levels during imbibition in order to identify ten candidate genes (TaGATA17/-25/-34/-37/-40/-46/-48/-51/-72/-73) that may be involved in the regulation of seed dormancy and germination in wheat. These findings provide valuable information for further dissection of TaGATA functions in the regulation of seed dormancy and germination, thereby enabling the improvement of wheat pre-harvest sprouting resistance by gene pyramiding.


Assuntos
Germinação , Oryza , Regulação da Expressão Gênica de Plantas , Germinação/genética , Dormência de Plantas/genética , Sementes/genética , Triticum/genética
10.
Gene ; 772: 145355, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33340562

RESUMO

Calanthe tsoongiana is a rare orchid species native to China. Asymbiotic seed germination is of great importance in the ex situ conservation of this species. Based on morphological characteristics and anatomical structures, the C. tsoongiana developmental process from seeds to seedlings was divided into four stages (SA, PB, PC and PD), and subsequently, changes in endogenous hormone contents and gene expression were assessed using RNA-seq analysis. K-means analysis divided the DEGs into eight clusters. The gene expression decreased markedly between the imbibed seed and globular protocorm stages, with this being the most notably enriched cluster. During the seed germination period, DEGs were dominated by ATP metabolic processes, respiration and photosynthesis. A small change in gene expression was found in the globular protocorm versus the finger-like protocorm stages. During the last developmental stage, DEGs were significantly enriched in lignin catabolic processes and plant-type secondary cell wall biogenesis. DEG homologs, such as TSA1, DAO, NCED1, STM, and CUC2, were related to phytohormones and the morphogenesis of shoots, leaves and roots. Particularly, interactions between CUC2 and STM as well as AS1 and STM were likely involved in protocorm formation and development. Furthermore, TSA1 and DAO were distinctly validated and implicated in the synthesis and metabolism of auxin, which has a pivotal role in plant development. Our study is the first to combine morphological and transcriptome analysis to examine the process of protocorm formation and development. The results provide a foundation for understanding the mechanisms of seed germination and protocorm development of C. tsoongiana.


Assuntos
Perfilação da Expressão Gênica/métodos , Orchidaceae/crescimento & desenvolvimento , Proteínas de Plantas/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Germinação , Orchidaceae/genética , Fotossíntese , Sementes/genética , Sementes/crescimento & desenvolvimento , Análise de Sequência de RNA
11.
Mol Cell ; 80(4): 607-620.e12, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33113344

RESUMO

Aberrant mitophagy has been implicated in a broad spectrum of disorders. PINK1, Parkin, and ubiquitin have pivotal roles in priming mitophagy. However, the entire regulatory landscape and the precise control mechanisms of mitophagy remain to be elucidated. Here, we uncover fundamental mitophagy regulation involving PINK1 and a non-canonical role of the mitochondrial Tu translation elongation factor (TUFm). The mitochondrion-cytosol dual-localized TUFm interacts with PINK1 biochemically and genetically, which is an evolutionarily conserved Parkin-independent route toward mitophagy. A PINK1-dependent TUFm phosphoswitch at Ser222 determines conversion from activating to suppressing mitophagy. PINK1 modulates differential translocation of TUFm because p-S222-TUFm is restricted predominantly to the cytosol, where it inhibits mitophagy by impeding Atg5-Atg12 formation. The self-antagonizing feature of PINK1/TUFm is critical for the robustness of mitophagy regulation, achieved by the unique kinetic parameters of p-S222-TUFm, p-S65-ubiquitin, and their common kinase PINK1. Our findings provide new mechanistic insights into mitophagy and mitophagy-associated disorders.


Assuntos
Drosophila melanogaster/crescimento & desenvolvimento , Mitocôndrias/patologia , Proteínas Mitocondriais/metabolismo , Mitofagia , Fator Tu de Elongação de Peptídeos/metabolismo , Proteínas Quinases/metabolismo , Animais , Citosol/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , Células HeLa , Humanos , Masculino , Mitocôndrias/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Fator Tu de Elongação de Peptídeos/genética , Fosforilação , Domínios e Motivos de Interação entre Proteínas , Proteínas Quinases/genética , Transporte Proteico , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
12.
Chem Commun (Camb) ; 55(34): 4989-4992, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-30968889

RESUMO

Hollow porous rhodium (Rh) nanoballs are prepared via a facile one-pot reaction. They are porous and possess dendritic exteriors, and it is easy to get them with a clean surface. Owing to the structrual advantages, they exhibit superior electrochemical catalytic activity and structural stability to the commercial Pt black towards ethanol electro-oxidation in alkaline medium.

13.
J Am Chem Soc ; 140(36): 11232-11240, 2018 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-30117323

RESUMO

Developing active and durable electro-catalysts toward ethanol oxidation reaction (EOR) with high selectivity toward the C-C bond cleavage is an important issue for the commercialization of direct ethanol fuel cell. Unfortunately, current ethanol oxidation electro-catalysts (e.g., Pt, Pd) still suffer from poor selectivity for direct oxidation of ethanol to CO2, and rapid activity degradation. Here we report a facile route to the synthesis of a new kind of cyclic penta-twinned (CPT) Rh nanostructures that are self-supported nanobranches (NBs) built with 1-dimension CPT nanorods as subunits. Structurally, the as-prepared Rh NBs possess high percentage of open {100} facets with significant CPT-induced lattice strains. With these unique structural characteristics, the as-prepared CPT Rh NBs exhibit outstanding electrocatalytic performance toward EOR in alkaline solution. Most strikingly, the selectivity of complete conversion ethanol to CO2 on the CPT Rh NBs is measured to be as high as 14.5 ± 1.1% at -0.15 V, far exceeding that for single-crystal tetrahedral nanocrystals, icosahedral nanocrystals, and commercial Rh black, as well as majority of reported values for Pt or Pd-based electro-catalysts. By combining with density functional theory calculation, the effects of different structural features of Rh on EOR are definitively elucidated. It was found that the large amount of open Rh (100) facets dominantly contribute to the outstanding activity and exceptionally high selectivity, while the additional tensile strain on (100) planes can further boost the catalytic activity by enhancing the adsorption strength and lowering the reaction barrier of dehydrogenation process of ethanol. As a proof of concept, the present work shows that rationally optimizing surface and electronic structure of electro-catalysts by simultaneously engineering their surface and bulk structures is a promising strategy to promote the performance of electro-catalysts.

14.
Org Lett ; 20(13): 3728-3731, 2018 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-29923730

RESUMO

An NBS-induced intramolecular cycloaromatization for the synthesis of 10-phenanthrenols from electron-withdrawing group substituted 1-biphenyl-2-ylethanones is described. The in situ generated bromide was designed to act as an initiator for the radical C-H bond activation. An oxidative cross-dehydrogenative coupling reaction of a highly active C-H bond with an inert C-H bond readily occurs under mild conditions without the need for transition metals or strong oxidants.

15.
Org Lett ; 19(23): 6344-6347, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29148795

RESUMO

Bromide-mediated intermolecular annulation of phenylethanone derivatives with alkynes has been developed, which allows for the regioselective formation of polysubstituted 1-naphthols. The usage of readily available bromine catalyst, broad substrate scope, and mild conditions make this protocol very practical. Mechanistic investigations reveal that the bromination of phenylethanone derivatives occurs to yield bromo-substituted intermediates, which react in situ with alkynes to furnish the desired 1-naphthols.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA