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1.
J Chemother ; 36(3): 202-207, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37599456

RESUMO

Because of lacking of head-to-head comparison between venetoclax and IDH1/IDH2 inhibitors (ivosidenib/enasidenib) for newly diagnosed unfit patients with acute myeloid leukemia (AML), the optimal option for these patients still remains undefined. We searched relevant published reports. Three RCTs with 180 IDH1 mutant and 165 IDH2 mutant patients were identified. Indirect comparison of OS using fixed effects network meta-analysis (NMA) models indicated venetoclax plus azacitidine (Ven-Aza) significantly improved survival than enasidenib plus azacitidine (Ena-Aza) (HR:0.30, p = 0.005) for those newly diagnosed patients with AML and IDH2 Mutation. And, for those IDH2 mutation patients, Ven-Aza also had the highest probability of 98.3% (OS analysis) and 84.0% (CR/CRi analysis) to be the best intervention among these first-line treatment regimens (Ven-Aza, Ena-Aza and Aza). And, there was a favorable trend towards Ven-Aza in survival analysis (HR:0.69, p = 0.42), when compared to ivosidenib plus azacitidine (Ivo-Aza) for those newly diagnosed patients with AML and IDH1 Mutation. For those IDH1 Mutation, venetoclax plus azacitidine (Ven-Aza) had the highest probability of 65.8% (OS analysis) and 73.0% (CR/CRi analysis) to be the best intervention among these first-line treatment regimens (Ven-Aza, ivosidenib plus azacitidine (Ivo-Aza) and azacitidine (Aza)). In conclusion, venetoclax plus azacitidine could be a good option for unfit newly diagnosed patients with acute myeloid leukemia and IDH1/2 mutation. Considering our limits (only trial data-based network meta-analysis et al.), future trials directly comparing these regimens are warranted.


Assuntos
Aminopiridinas , Compostos Bicíclicos Heterocíclicos com Pontes , Glicina/análogos & derivados , Leucemia Mieloide Aguda , Piridinas , Sulfonamidas , Triazinas , Humanos , Metanálise em Rede , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Azacitidina/uso terapêutico , Mutação , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Isocitrato Desidrogenase/genética
2.
ACS Omega ; 8(25): 22496-22507, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37396234

RESUMO

Efficient and effective drug-target binding affinity (DTBA) prediction is a challenging task due to the limited computational resources in practical applications and is a crucial basis for drug screening. Inspired by the good representation ability of graph neural networks (GNNs), we propose a simple-structured GNN model named SS-GNN to accurately predict DTBA. By constructing a single undirected graph based on a distance threshold to represent protein-ligand interactions, the scale of the graph data is greatly reduced. Moreover, ignoring covalent bonds in the protein further reduces the computational cost of the model. The graph neural network-multilayer perceptron (GNN-MLP) module takes the latent feature extraction of atoms and edges in the graph as two mutually independent processes. We also develop an edge-based atom-pair feature aggregation method to represent complex interactions and a graph pooling-based method to predict the binding affinity of the complex. We achieve state-of-the-art prediction performance using a simple model (with only 0.6 M parameters) without introducing complicated geometric feature descriptions. SS-GNN achieves Pearson's Rp = 0.853 on the PDBbind v2016 core set, outperforming state-of-the-art GNN-based methods by 5.2%. Moreover, the simplified model structure and concise data processing procedure improve the prediction efficiency of the model. For a typical protein-ligand complex, affinity prediction takes only 0.2 ms. All codes are freely accessible at https://github.com/xianyuco/SS-GNN.

3.
Plant Physiol ; 193(1): 775-791, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37204820

RESUMO

Flowering time, maturity, and plant height are crucial agronomic traits controlled by photoperiod that affect soybean (Glycine max [L.] Merr.) yield and regional adaptability. It is important to cultivate soybean cultivars of earlier maturity that adapt to high latitudes. GAMYB-binding protein 1 (GmGBP1), a member of the SNW/SKIP family of transcriptional coregulators in soybean, is induced by short days and interacts with transcription factor GAMYB (GmGAMYB) during photoperiod control of flowering time and maturity. In the present study, GmGBP1:GmGBP1 soybean showed the phenotypes of earlier maturity and higher plant height. Chromatin immunoprecipitation sequencing (ChIP-seq) assays of GmGBP1-binding sites and RNA sequencing (RNA-seq) of differentially expressed transcripts in GmGBP1:GmGBP1 further identified potential targets of GmGBP1, including small auxin-up RNA (GmSAUR). GmSAUR:GmSAUR soybean also showed earlier maturity and higher plant height. GmGBP1 interacted with GmGAMYB, bound to the promoter of GmSAUR and promoted the expression of FLOWER LOCUS T homologs 2a (GmFT2a) and FLOWERING LOCUS D LIKE 19 (GmFDL19). Flowering repressors such as GmFT4 were negatively regulated, resulting in earlier flowering and maturity. Furthermore, the interaction of GmGBP1 with GmGAMYB increased the gibberellin (GA) signal to promote height and hypocotyl elongation by activating GmSAUR and GmSAUR bound to the promoter of the GA-positive activating regulator gibberellic acid-stimulated Arabidopsis 32 (GmGASA32). These results suggested a photoperiod regulatory pathway in which the interaction of GmGBP1 with GmGAMYB directly activated GmSAUR to promote earlier maturity and plant height in soybean.


Assuntos
Glycine max , Proteínas de Plantas , Fatores de Transcrição , Hipocótilo/metabolismo , Fotoperíodo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , RNA de Plantas/genética , Transdução de Sinais , Glycine max/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica
4.
Plant Physiol ; 191(4): 2427-2446, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36508351

RESUMO

Salt and drought stresses are major factors limiting soybean (Glycine max [L.] Merr.) growth and development; thus, improving soybean stress tolerance is critical. In this study, both salt stress and drought stress induced mRNA levels of CONSTANS-like 1a (GmCOL1a) and stabilized the GmCOL1a protein. Transgenic 35S:GmCOL1a soybean plants exhibited enhanced salt and drought tolerance, with higher relative water content in leaves, greater proline content, lower malondialdehyde (MDA) content, and less reactive oxygen species (ROS) production compared with wild-type plants; the GmCOL1a knockout co-9 mutant showed opposite phenotypes. In addition, GmCOL1a promoted the expression of genes related to salt tolerance, effectively reducing the Na+/K+ ratio in soybean plants, especially in stems and leaves of 35S:GmCOL1a soybean. Chromatin immunoprecipitation sequencing (ChIP-seq) analysis identified two potential direct targets of GmCOL1a, late embryogenesis abundant (GmLEA) and Δ1-pyrroline-5-carboxylate synthetase (GmP5CS) genes, which were verified by chromatin immunoprecipitation quantitative polymerase chain reaction (ChIP-qPCR), electrophoretic mobility shift assay (EMSA), and transient transcriptional activation assays. GmCOL1a bound directly to the Myc(bHLH)-binding and Che-binding motifs of GmLEA and GmP5CS promoters to stimulate mRNA expression. Analysis of transgenic hairy-root GmP5CS:GmP5CS soybean plants in wild type, co-9, and 35S:GmCOL1a backgrounds further revealed that GmCOL1a enhances salt and drought tolerance by promoting GmP5CS protein accumulation in transgenic soybean hairy roots. Therefore, we demonstrate that GmCOL1a plays an important role in tolerance to abiotic stress in soybean.


Assuntos
Resistência à Seca , Glycine max , Glycine max/metabolismo , Proteínas de Plantas/metabolismo , Estresse Salino , Tolerância ao Sal/genética , Estresse Fisiológico/genética , Secas , Plantas Geneticamente Modificadas/metabolismo , Regulação da Expressão Gênica de Plantas
5.
Macromol Rapid Commun ; 43(3): e2100643, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34755405

RESUMO

Nature has provided many delicate strategies for optimizing the structural characteristics of biological materials. One such strategy is the strengthening and toughening of matrix materials by aduandant and hierarchically arranged non-covalent crosslinking. However, efficient strengthening and toughening of high-performance aromatic polymers by non-covalent bonds has rarely been reported yet. Herein, we report the preparation and characterizations of a metal coordination bonds crosslinked polybenzimidazole (PBI) network. By optimizing the synthetic parameters, the strength of copper ion (Cu2+ ) crosslinked PBI is improved from 87.8 to 218.4 MPa, and the toughness is increased from 19.4 to 111.9 MJ m-3 , corresponding to increments of 148.7 % and 476.8 %, respectively, which surpass all previously reported non-covalent bonds crosslinked high-performance polymers. PBI with varied chain flexibility are then synthesized to deeply understand the stregnening and toughening mechanism. In addition, the glass transition temperature of PBI is dramatically increased by 75 °C after Cu2+ crosslinking. Moreover, the chemical recycling of PBI from crosslinekd network, and the development of a novel high-temperature resistant or high-temperature rewritable anti-counterfeiting films based on Cu2+ crosslinked PBI are also demonstrated. This study is expected to shed light on design principle for future supramolecularly crosslinked and recyclable high-performance polymers.


Assuntos
Cobre , Polímeros , Íons , Temperatura , Temperatura de Transição
6.
Int J Mol Sci ; 22(19)2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34638672

RESUMO

Flowering is an important developmental process from vegetative to reproductive growth in plant; thus, it is necessary to analyze the genes involved in the regulation of flowering time. The MADS-box transcription factor family exists widely in plants and plays an important role in the regulation of flowering time. However, the molecular mechanism of GmFULc involved in the regulation of plant flowering is not very clear. In this study, GmFULc protein had a typical MADS domain and it was a member of MADS-box transcription factor family. The expression analysis revealed that GmFULc was induced by short days (SD) and regulated by the circadian clock. Compared to wild type (WT), overexpression of GmFULc in transgenic Arabidopsis caused significantly earlier flowering time, while ful mutants flowered later, and overexpression of GmFULc rescued the late-flowering phenotype of ful mutants. ChIP-seq of GmFULc binding sites identified potential direct targets, including TOPLESS (TPL), and it inhibited the transcriptional activity of TPL. In addition, the transcription levels of FLOWERING LOCUS T (FT), SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 (SOC1) and LEAFY (LFY) in the downstream of TPL were increased in GmFULc- overexpressionArabidopsis, suggesting that the early flowering phenotype was associated with up-regulation of these genes. Our results suggested that GmFULc inhibited the transcriptional activity of TPL and induced expression of FT, SOC1 and LFY to promote flowering.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Glycine max/genética , Plantas Geneticamente Modificadas/genética , Relógios Circadianos/genética , Flores/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação da Expressão Gênica de Plantas/genética , Fotoperíodo , Folhas de Planta/genética , Reprodução/genética
7.
Sci Total Environ ; 706: 135872, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31855628

RESUMO

The fall armyworm (Spodoptera frugiperda J.E. Smith) is one of the most notorious pests of several crops in the world. However, to date, few studies have simulated the future distribution patterns of fall armyworm under rapid global changes. Though the relative influences of climate and land-use on species distribution might depend on the spatial scales of the studies, it is not known whether this rule is applicable to pests which mostly feed on crops. Here, we developed MaxEnt models to explore the distribution patterns of fall armyworm, as well as the relative influences of land-use change, topography and climate change on them. Under the present conditions and scenarios of RCP 2.6 and 8.5 (the most optimistic and pessimistic emissions scenarios, respectively), high potential habitats of fall armyworm were mostly recorded along the east coast areas of the USA, the State of Florida, Mexico, Central America, southern part of Brazil, central Africa, and southern Asia. Among all of the continents, Africa will face the greatest increase of the threats from fall armyworm in future. Under RCP 2.6 scenario, both the potential habitats and areas with increased habitat suitability were larger than those under RCP 8.5. Therefore, much more effort is required to control fall armyworm under RCP 2.6 scenario. Compared to climate change, land-use changes are more important in shaping the distribution patterns of fall armyworm. Therefore, the concentration of resources might modify the relative influence of climate and land-use in species distributions at large scales. Thus, regulating land-use might prove effective for mitigating the proliferation of fall armyworm. In general, C4 annual crops and managed pastures provide more suitable habitats for fall armyworm than C3 annual crops. Our findings demonstrate that delineating resource concentrations could provide a new approach towards controlling fall armyworm under current and future global change.


Assuntos
Spodoptera , Animais
8.
Proc Natl Acad Sci U S A ; 116(14): 7137-7146, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30894495

RESUMO

Crucihimalaya himalaica, a close relative of Arabidopsis and Capsella, grows on the Qinghai-Tibet Plateau (QTP) about 4,000 m above sea level and represents an attractive model system for studying speciation and ecological adaptation in extreme environments. We assembled a draft genome sequence of 234.72 Mb encoding 27,019 genes and investigated its origin and adaptive evolutionary mechanisms. Phylogenomic analyses based on 4,586 single-copy genes revealed that C. himalaica is most closely related to Capsella (estimated divergence 8.8 to 12.2 Mya), whereas both species form a sister clade to Arabidopsis thaliana and Arabidopsis lyrata, from which they diverged between 12.7 and 17.2 Mya. LTR retrotransposons in C. himalaica proliferated shortly after the dramatic uplift and climatic change of the Himalayas from the Late Pliocene to Pleistocene. Compared with closely related species, C. himalaica showed significant contraction and pseudogenization in gene families associated with disease resistance and also significant expansion in gene families associated with ubiquitin-mediated proteolysis and DNA repair. We identified hundreds of genes involved in DNA repair, ubiquitin-mediated proteolysis, and reproductive processes with signs of positive selection. Gene families showing dramatic changes in size and genes showing signs of positive selection are likely candidates for C. himalaica's adaptation to intense radiation, low temperature, and pathogen-depauperate environments in the QTP. Loss of function at the S-locus, the reason for the transition to self-fertilization of C. himalaica, might have enabled its QTP occupation. Overall, the genome sequence of C. himalaica provides insights into the mechanisms of plant adaptation to extreme environments.


Assuntos
Adaptação Fisiológica/genética , Altitude , Arabidopsis/genética , Brassicaceae/genética , Genes de Plantas/genética , Aclimatação/genética , Aclimatação/fisiologia , Adaptação Fisiológica/fisiologia , Arabidopsis/fisiologia , Brassicaceae/fisiologia , Capsella/genética , Capsella/fisiologia , Mudança Climática , Reparo do DNA/genética , Resistência à Doença/genética , Ambientes Extremos , Dosagem de Genes , Genes de Plantas/fisiologia , Proteínas Nucleares/genética , Filogenia , Proteínas de Plantas/genética , Seleção Genética , Autofertilização/genética , Alinhamento de Sequência , Tibet , Sequenciamento Completo do Genoma
9.
J Colloid Interface Sci ; 529: 130-138, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29886225

RESUMO

Double-shell hollow particles (DSHPs) have attracted significant attention due to their diverse potential applications. DSHPs are usually obtained by multi-step sacrificial template method which is tedious and inefficient. In this work, a facile synthesis of silica DSHPs has been developed via a novel one-step template method, which is using single-hole hollow particles (SHHPs) as the templates. The shapes and internal structures of the DSHPs were determined by SEM and TEM, and the average diameters of inner and outer shells were about 0.6 and 1.6 µm, respectively. According to FTIR analyses, the compositions of silica DSHPs were identified as well. Furthermore, the silica DSHPs was applied to Li-ion batteries as a modifier of gel polymer electrolyte (GPEs), and the results showed that the gel composite electrolytes (GCEs) could display higher capability, higher ionic conductivity and better rate performance at high current density for GCEs-cell. Properties of the silica DSHPs such as larger specific surface area, more porous structures and Lewis acid-base effect were important for high-performance Li-ion batteries.

10.
Appl Plant Sci ; 5(3)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28337389

RESUMO

PREMISE OF THE STUDY: Ephedragerardiana (Ephedraceae), occurring in the Himalayan ranges, is an important plant species used in Tibetan medicine. Due to the lack of molecular markers to characterize genetic diversity, knowledge for conservation and uses of E. gerardiana resources is limited; we therefore developed microsatellite markers for use in this species. METHODS AND RESULTS: Using Illumina MiSeq sequencing technology, we developed 29 polymorphic microsatellite loci suitable for E. gerardiana, of which 15 loci also showed polymorphisms in two related Ephedra species, E. saxatilis and E. monosperma. The average number of effective alleles per locus ranged from two to six. The observed and expected heterozygosity ranged from 0.23 to 0.83 and 0.44 to 0.86, respectively, in E. gerardiana populations. CONCLUSIONS: The developed 29 microsatellite markers are effective for the study of genetic structure and genetic diversity of E. gerardiana, and 15 of these markers are suitable for related Ephedra species.

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