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1.
Proc Natl Acad Sci U S A ; 121(19): e2318652121, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38687781

RESUMO

Water oxidation on magnetic catalysts has generated significant interest due to the spin-polarization effect. Recent studies have revealed that the disappearance of magnetic domain wall upon magnetization is responsible for the observed oxygen evolution reaction (OER) enhancement. However, an atomic picture of the reaction pathway remains unclear, i.e., which reaction pathway benefits most from spin-polarization, the adsorbent evolution mechanism, the intermolecular mechanism (I2M), the lattice oxygen-mediated one, or more? Here, using three model catalysts with distinguished atomic chemistries of active sites, we are able to reveal the atomic-level mechanism. We found that spin-polarized OER mainly occurs at interconnected active sites, which favors direct coupling of neighboring ligand oxygens (I2M). Furthermore, our study reveals the crucial role of lattice oxygen participation in spin-polarized OER, significantly facilitating the coupling kinetics of neighboring oxygen radicals at active sites.

2.
Angew Chem Int Ed Engl ; 63(11): e202317957, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38270335

RESUMO

Weak adsorption of gas reactants and strong binding of intermediates present a significant challenge for most transition metal oxides, particularly in the realm of CO2 photoreduction. Herein, we demonstrate that the adsorption can be fine-tuned by phase engineering of oxide catalysts. An oxygen vacancy mediated topological phase transition in Ni-Co oxide nanowires, supported on a hierarchical graphene aerogel (GA), is observed from a spinel phase to a rock-salt phase. Such in situ phase transition empowers the Ni-Co oxide catalyst with a strong internal electric field and the attainment of abundant oxygen vacancies. Among a series of catalysts, the in situ transformed spinel/rock-salt heterojunction supported on GA stands out for an exceptional photocatalytic CO2 reduction activity and selectivity, yielding an impressive CO production rate of 12.5 mmol g-1 h-1 and high selectivity of 96.5 %. This remarkable performance is a result of the robust interfacial coupling between two topological phases that optimizes the electronic structures through directional charge transfer across interfaces. The phase transition process induces more Co2+ in octahedral site, which can effectively enhance the Co-O covalency. This synergistic effect balances the surface activation of CO2 molecules and desorption of reaction intermediates, thereby lowering the energetic barrier of the rate-limiting step.

3.
J Mater Chem B ; 12(3): 658-666, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-37934458

RESUMO

Asymmetric carbon has emerged as an important material to enrich morphologies as well as enhance functions for bioapplications. Here, asymmetric mesoporous carbon hemispheres (CHS) integrated with γ-Fe2O3 and GdPO4 (Fe-Gd) nanoparticles are proposed and prepared for potential imaging-guided photothermal therapy (PTT). Interestingly, Fe-Gd/CHS contributes to an almost 1.5 times enhancement in light harvesting and photothermal conversion efficiency as compared with its corresponding spherical analogue. The possible underlying mechanism is discussed in view of the unique asymmetric structure-featured carbon. Further identification of the inherited photoacoustic (PA) and magnetic resonance (MR) imaging properties leads to the consequent in vivo evaluation of its imaging and PTT performances, which demonstrates its capability as a function-integrated system for potential theranostics.


Assuntos
Nanopartículas , Terapia Fototérmica , Fototerapia , Carbono , Imageamento por Ressonância Magnética
4.
Cardiovasc Toxicol ; 23(11-12): 364-376, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37787964

RESUMO

A growing concern of cardiotoxicity induced by PI3K inhibitors has raised the requirements to evaluate the structure-cardiotoxicity relationship (SCR) in the development process of novel inhibitors. Based on three bioisosteric 7-azaindazole-based candidate inhibitors namely FD269, FD268 and FD274 that give same order of inhibitory concentration 50% (IC50) magnitude against PI3Ks, in this work, we proposed to systematically evaluate the SCR of 7-azaindazole-based PI3K inhibitors designed by bioisosteric approach. The 24-h lethal concentrations 50% (LC50) of FD269, FD268 and FD274 against zebrafish embryos were 0.35, 4.82 and above 50 µM (not detected), respectively. Determination of the heart rate, pericardial and yolk-sac areas and vascular malformation confirmed the remarkable reduction in the cardiotoxicity of from FD269 to FD268 and to FD274. The IC50s of all three compounds against the hERG channel were tested on the CHO cell line that constitutively expressing hERG channel, which were all higher than 20 µM. The transcriptomic analysis revealed that FD269 and FD268 induced the up-regulation of noxo1b, which encodes a subunit of an NADPH oxidase evoking the oxidative stress. Furthermore, immunohistochemistry tests confirmed the structure-dependent attenuation of the overproduction of ROS and cardiac apoptosis. Our results verified the feasibility of bioisosteric replacement to attenuate the cardiotoxicity of 7-azaindazole-based PI3K inhibitors, suggesting that the screening for PI3K inhibitors with both high potency and low cardiotoxicity from bioisosteres would be a beneficial trial.


Assuntos
Cardiotoxicidade , Peixe-Zebra , Animais , Cardiotoxicidade/metabolismo , Peixe-Zebra/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Embrião não Mamífero/metabolismo , Coração
5.
Small ; 19(48): e2303063, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37415511

RESUMO

Nanoscale metal-organic frameworks (nanoMOFs) are emerging as an important class of nanomaterials for the systematical investigation of biomedically relevant structure-property relationship (SPR) due to their highly tailorable features. In this work, the reticular chemistry approach is shown to explore the SPR of a fcu-type Zr(IV)-nanoMOF for T1 -weighted magnetic resonance imaging (MRI). Isoreticular replacement of the eight-coordinated square-antiprismatic Zr(IV) by nine-coordinated Gd(III) brings a stoichiometric water capped on the square-antiprismatic site, enabling the relaxation transfer in the inner-sphere, giving the r1 value of 4.55 mM-1 ·s-1 at the doping ratio of Gd : Zr = 1 : 1. Then, these isoreticular engineering studies provide feasible ways to facilitate the relaxation transfer in the second- and outer-sphere of the Gd(III)-doped Zr-oxo cluster for the relaxation respectively. Finally, these in vitro and in vivo MRI studies revealed that the Gd(III)-doped Zr-oxo cluster aggregated underlying the fcu-type framework surpasses its discrete molecular cluster for MRI. These results demonstrated that there is plenty of room inside MOFs for T1 -weighted MRI by reticular chemistry.

6.
Plant Physiol Biochem ; 201: 107795, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37301186

RESUMO

Although mainly known for producing artemisinin, Artemisia annua is enriched in phenylpropanoid glucosides (PGs) with significant bioactivities. However, the biosynthesis of A. annua PGs is insufficiently investigated. Different A. annua ecotypes from distinct growing environments accumulate varying amounts of metabolites, including artemisinin and PGs such as scopolin. UDP-glucose:phenylpropanoid glucosyltransferases (UGTs) transfers glucose from UDP-glucose in PG biosynthesis. Here, we found that the low-artemisinin ecotype GS produces a higher amount of scopolin, compared to the high-artemisinin ecotype HN. By combining transcriptome and proteome analyses, we selected 28 candidate AaUGTs from 177 annotated AaUGTs. Using AlphaFold structural prediction and molecular docking, we determined the binding affinities of 16 AaUGTs. Seven of the AaUGTs enzymatically glycosylated phenylpropanoids. AaUGT25 converted scopoletin to scopolin and esculetin to esculin. The lack of accumulation of esculin in the leaf and the high catalytic efficiency of AaUGT25 on esculetin suggest that esculetin is methylated to scopoletin, the precursor of scopolin. We also discovered that AaOMT1, a previously uncharacterized O-methyltransferase, converts esculetin to scopoletin, suggesting an alternative route for producing scopoletin, which contributes to the high-level accumulation of scopolin in A. annua leaves. AaUGT1 and AaUGT25 responded to induction of stress-related phytohormones, implying the involvement of PGs in stress responses.


Assuntos
Artemisia annua , Artemisininas , Artemisia annua/metabolismo , Escopoletina/química , Escopoletina/metabolismo , Escopoletina/farmacologia , Esculina/metabolismo , Multiômica , Simulação de Acoplamento Molecular , Artemisininas/metabolismo , Glucosídeos/metabolismo , Glucose/metabolismo , Difosfato de Uridina/metabolismo
7.
Eur J Med Chem ; 257: 115514, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37262997

RESUMO

Despite the recent development of PIM inhibitors based on N-(pyridin-3-yl)acetamide scaffold for acute myeloid leukemia (AML), the structural-activity relationship (SAR) associated with the effects of positional isomerization of N toward to Lys67 and freedom of solvent fragment toward to Asp128/Glu171 still remains an open question. In this work, a structurally novel compound based on N-pyridinyl amide was designed by fragment hybridization and then our SAR exploration revealed that the positional isomerization would lead to a decrease in activity, while increase of the freedom of solvent fragment by breaking the intramolecular hydrogen bond unprecedentedly leads to an increase in activity. These studies finally resulted in the screening out of a potent PIM inhibitor FD1024 (compound 24) which exerts strong antiproliferative activity against the tested AML cell lines and achieves profound antitumor efficacy in mice at well-tolerated dose schedules.


Assuntos
Antineoplásicos , Leucemia Mieloide Aguda , Camundongos , Animais , Proteínas Proto-Oncogênicas c-pim-1 , Amidas/farmacologia , Amidas/uso terapêutico , Linhagem Celular Tumoral , Antineoplásicos/química , Leucemia Mieloide Aguda/patologia , Inibidores de Proteínas Quinases/química
8.
Eur J Med Chem ; 258: 115543, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37329712

RESUMO

PI3K-Akt-mTOR pathway is a highly activated signal transduction pathway in human hematological malignancies and has been validated as a promising target for acute myeloid leukemia (AML) therapy. Herein, we designed and synthesized a series of 7-azaindazole derivatives as potent PI3K/mTOR dual inhibitors based on our previously reported FD223. Among them, compound FD274 showed excellent dual PI3K/mTOR inhibitory activity, with IC50 values against PI3Kα/ß/γ/δ and mTOR of 0.65 nM, 1.57 nM, 0.65 nM, 0.42 nM, and 2.03 nM, respectively, superior to compound FD223. Compared to the positive drug Dactolisib, FD274 exhibited significant anti-proliferation of AML cell lines (HL-60 and MOLM-16 with IC50 values of 0.092 µM and 0.084 µM, respectively) in vitro. Furthermore, FD274 demonstrated dose-dependent inhibition of tumor growth in the HL-60 xenograft model in vivo, with 91% inhibition of tumor growth at an intraperitoneal injection dose of 10 mg/kg and no observable toxicity. All of these results suggest that FD274 has potential for further development as a promising PI3K/mTOR targeted anti-AML drug candidate.


Assuntos
Antineoplásicos , Leucemia Mieloide Aguda , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Serina-Treonina Quinases TOR/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/patologia , Linhagem Celular Tumoral , Proliferação de Células , Inibidores de Proteínas Quinases/metabolismo
9.
Angew Chem Int Ed Engl ; 62(26): e202301721, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37130000

RESUMO

The reaction kinetics of spin-polarized oxygen evolution reaction (OER) can be enhanced by ferromagnetic (FM) catalysts under an external magnetic field. However, applying a magnetic field necessitates additional energy consumption and creates design difficulties for OER. Herein, we demonstrate that a single-domain FM catalyst without external magnetic fields exhibits a similar OER increment to its magnetized multi-domain one. The evidence is given by comparing the pH-dependent increment of OER on multi- and single-domain FM catalysts with or without a magnetic field. The intrinsic activity of a single-domain catalyst is higher than that of a multi-domain counterpart. The latter can be promoted to approach the former by the magnetization effect. Reducing the FM catalyst size into the single-domain region, the spin-polarized OER performance can be achieved without a magnetic field, illustrating an external magnetic field is not a requirement to reap the benefits of magnetic catalysts.


Assuntos
Campos Magnéticos , Oxigênio , Cinética , Oxirredução , Água
10.
Nat Commun ; 14(1): 2482, 2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37120590

RESUMO

Magnetization promoted activity of magnetic catalysts towards the oxygen evolution reaction (OER) has attracted great attention, but remains a puzzle where the increment comes from. Magnetization of a ferromagnetic material only changes its magnetic domain structure. It does not directly change the spin orientation of unpaired electrons in the material. The confusion is that each magnetic domain is a small magnet and theoretically the spin-polarization promoted OER already occurs on these magnetic domains, and thus the enhancement should have been achieved without magnetization. Here, we demonstrate that the enhancement comes from the disappeared domain wall upon magnetization. Magnetization leads to the evolution of the magnetic domain structure, from a multi-domain one to a single domain one, in which the domain wall disappears. The surface occupied by the domain wall is reformatted into one by a single domain, on which the OER follows the spin-facilitated pathways and thus the overall increment on the electrode occurs. This study fills the missing gap for understanding the spin-polarized OER and it further explains the type of ferromagnetic catalysts which can give increment by magnetization.

11.
Adv Mater ; 35(2): e2207041, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36281800

RESUMO

Water electrolysis is a promising technique for carbon neutral hydrogen production. A great challenge remains at developing robust and low-cost anode catalysts. Many pre-catalysts are found to undergo surface reconstruction to give high intrinsic activity in the oxygen evolution reaction (OER). The reconstructed oxyhydroxides on the surface are active species and most of them outperform directly synthesized oxyhydroxides. The reason for the high intrinsic activity remains to be explored. Here, a study is reported to showcase the unique reconstruction behaviors of a pre-catalyst, thiospinel CoFe2 S4 , and its reconstruction chemistry for a high OER activity. The reconstruction of CoFe2 S4 gives a mixture with both Fe-S component and active oxyhydroxide (Co(Fe)Ox Hy ) because Co is more inclined to reconstruct as oxyhydroxide, while the Fe is more stable in Fe-S component in a major form of Fe3 S4 . The interface spin channel is demonstrated in the reconstructed CoFe2 S4 , which optimizes the energetics of OER steps on Co(Fe)Ox Hy species and facilitates the spin sensitive electron transfer to reduce the kinetic barrier of O-O coupling. The advantage is also demonstrated in a membrane electrode assembly (MEA) electrolyzer. This work introduces the feasibility of engineering the reconstruction chemistry of the precatalyst for high performance and durable MEA electrolyzers.

12.
Genome ; 66(2): 34-50, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36516428

RESUMO

Periploca forrestii, a medicinal plant of the family Apocynaceae, is known as an effective and widely used clinical prescription for the treatment of rheumatoid diseases. In this study, we de novo sequenced and assembled the completement chloroplast (cp) genome of P. forrestii based on combined Oxford Nanopore PromethION and Illumina data. The cp genome was 153 724 bp in length and had four subregions. Moreover, an 84 433 bp large single-copy and a 17 731 bp small single-copy were separated by 25 780 bp inverted repeats (IRs). The cp genome included 132 genes with 18 duplicates in the IRs. A total of 45 repeat structures and 183 simple sequence repeats were detected. Codon usage showed a bias toward A/T-ending codons. A comparative study of Apocynaceae revealed that an IR expansion occurred on P. forrestii. The Ka/Ks values of eight species of Apocynaceae suggested that positive selection was exerted on the psaI and ycf2 genes, which might reflect specific adaptions to the P. forrestii particular growth environment. Phylogenetic analysis indicated that Periplocoideae was a sister to Asclepiadoideae, forming a monophyletic group in the family Apocynaceae. This study provided an important P. forrestii genomic resource for future evolutionary studies and the phylogenetic reconstruction of the family Apocynaceae.


Assuntos
Genoma de Cloroplastos , Periploca , Periploca/genética , Filogenia , Genômica , Evolução Molecular
13.
PLoS One ; 17(11): e0277893, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36413544

RESUMO

Aberration of PI3K signaling pathway has been confirmed to be associated with several hematological malignancies including acute myeloid leukemia (AML). FD268, a pyridinesulfonamide derivative characterized by the conjugation of 7-azaindole group, is a newly identified PI3K inhibitor showing high potent enzyme activity at nanomole concentration. In this study, we demonstrated that FD268 dose-dependently inhibits survival of AML cells with the efficacy superior to that of PI-103 (pan-PI3K inhibitor) and CAL-101 (selective PI3Kδ inhibitor) in the tested HL-60, MOLM-16, Mv-4-11, EOL-1 and KG-1 cell lines. Further mechanistic studies focused on HL-60 revealed that FD268 significantly inhibits the PI3K/Akt/mTOR signaling pathway, promotes the activation of pro-apoptotic protein Bad and downregulates the expression of anti-apoptotic protein Mcl-1, thus suppressing the cell proliferation and inducing caspase-3-dependent apoptosis. The bioinformatics analysis of the transcriptome sequencing data also indicated a potential involvement of the PI3K/Akt/mTOR pathway. These studies indicated that FD268 possesses high potent activity toward AML cells via inhibition of PI3K/Akt/mTOR signaling pathway, which sheds some light on the pyridinesulfonamide scaffold for further optimization and investigation.


Assuntos
Leucemia Mieloide Aguda , Fosfatidilinositol 3-Quinases , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Apoptose , Proliferação de Células , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Leucemia Mieloide Aguda/tratamento farmacológico
14.
Adv Sci (Weinh) ; 9(36): e2204624, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36285805

RESUMO

Heat is abundantly available from various sources including solar irradiation, geothermal energy, industrial processes, automobile exhausts, and from the human body and other living beings. However, these heat sources are often overlooked despite their abundance, and their potential applications remain underdeveloped. In recent years, important progress has been made in the development of high-performance thermoelectric materials, which have been extensively studied at medium and high temperatures, but less so at near room temperature. Silver-based chalcogenides have gained much attention as near room temperature thermoelectric materials, and they are anticipated to catalyze tremendous growth in energy harvesting for advancing internet of things appliances, self-powered wearable medical systems, and self-powered wearable intelligent devices. This review encompasses the recent advancements of thermoelectric silver-based chalcogenides including binary and multinary compounds, as well as their hybrids and composites. Emphasis is placed on strategic approaches which improve the value of the figure of merit for better thermoelectric performance at near room temperature via engineering material size, shape, composition, bandgap, etc. This review also describes the potential of thermoelectric materials for applications including self-powering wearable devices created by different approaches. Lastly, the underlying challenges and perspectives on the future development of thermoelectric materials are discussed.


Assuntos
Prata , Dispositivos Eletrônicos Vestíveis , Humanos , Catálise , Engenharia , Temperatura Alta
15.
Nanoscale Adv ; 4(5): 1414-1421, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36133683

RESUMO

The size modulation of hollow carbon nanospheres (HCSs) has attracted great interest in the contexts of cellular uptake, drug delivery and bioimaging. In this study, a facile fabrication method was specifically used to minimize all influencing factors except for the particle size. A series of nanoparticles of hollow carbon nanospheres embedded with magnetic resonance imaging (MRI) nanoagent γ-Fe2O3 and GdPO4 nanoparticles (Fe-Gd/HCS), were successfully prepared and applied to in vitro/vivo evaluation with well-defined sizes of ∼100 nm (Fe-Gd/HCS-S), ∼200 nm (Fe-Gd/HCS-M), and ∼300 nm (Fe-Gd/HCS-L), respectively. Then the in vitro size effect of Fe-Gd/HCS was systematically investigated by bio-TEM, CLSM, CCK-8 assay, and flow cytometry revealing that Fe-Gd/HCS could be internalized and the cellular uptake amounts increase with the decrease of size. Furthermore, the in vivo size-effect behavior of Fe-Gd/HCS (∼100 nm, ∼200 nm, ∼300 nm) was tracked by MRI technique, demonstrating that all Fe-Gd/HCS can distinguish the liver, in which Fe-Gd/HCS with the smallest particle size exhibited the best performance among these nanoparticles. By leveraging on these features, Fe-Gd/HCS-S (∼100 nm) was further chosen as a theranostic agent, preliminarily presenting its capability for multi-modal imaging and therapy.

16.
Microb Cell Fact ; 21(1): 195, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36123741

RESUMO

BACKGROUND: Karst-adapted plant, Lysionotus pauciflours accumulates special secondary metabolites with a wide range of pharmacological effects for surviving in drought and high salty areas, while researchers focused more on their environmental adaptations and evolutions. Nevadensin (5,7-dihydroxy-6,8,4'-trimethoxyflavone), the main active component in L. pauciflours, has unique bioactivity of such as anti-inflammatory, anti-tubercular, and anti-tumor or cancer. Complex decoration of nevadensin, such as hydroxylation and glycosylation of the flavone skeleton determines its diversity and biological activities. The lack of omics data limits the exploration of accumulation mode and biosynthetic pathway. Herein, we integrated transcriptomics, metabolomics, and microbial recombinant protein system to reveal hydroxylation and glycosylation involving nevadensin biosynthesis in L. pauciflours. RESULTS: Up to 275 flavonoids were found to exist in L. pauciflorus by UPLC-MS/MS based on widely targeted metabolome analysis. The special flavone nevadensin (5,7-dihydroxy-6,8,4'-trimethoxyflavone) is enriched in different tissues, as are its related glycosides. The flavonoid biosynthesis pathway was drawn based on differential transcripts analysis, including 9 PAL, 5 C4H, 8 4CL, 6 CHS, 3 CHI, 1 FNSII, and over 20 OMTs. Total 310 LpCYP450s were classified into 9 clans, 36 families, and 35 subfamilies, with 56% being A-type CYP450s by phylogenetic evolutionary analysis. According to the phylogenetic tree with AtUGTs, 187 LpUGTs clustered into 14 evolutionary groups (A-N), with 74% being E, A, D, G, and K groups. Two LpCYP82D members and LpUGT95 were functionally identified in Saccharomyces cerevisiae and Escherichia coli, respectively. CYP82D-8 and CYP82D-1 specially hydroxylate the 6- or 8-position of A ring in vivo and in vitro, dislike the function of F6H or F8H discovered in basil which functioned depending on A-ring substituted methoxy. These results refreshed the starting mode that apigenin can be firstly hydroxylated on A ring in nevadensin biosynthesis. Furthermore, LpUGT95 clustered into the 7-OGT family was verified to catalyze 7-O glucosylation of nevadensin accompanied with weak nevadensin 5-O glucosylation function, firstly revealed glycosylation modification of flavones with completely substituted A-ring. CONCLUSIONS: Metabolomic and full-length transcriptomic association analysis unveiled the accumulation mode and biosynthetic pathway of the secondary metabolites in the karst-adapted plant L. pauciflorus. Moreover, functional identification of two LpCYP82D members and one LpUGT in microbe reconstructed the pathway of nevadensin biosynthesis.


Assuntos
Apigenina , Flavonas , Cromatografia Líquida , Flavonas/metabolismo , Flavonoides , Glicosídeos , Glicosilação , Humanos , Hidroxilação , Filogenia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Espectrometria de Massas em Tandem
17.
Front Biosci (Landmark Ed) ; 27(8): 236, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-36042168

RESUMO

BACKGROUND: Gentiana plants, which have great medicinal and ornamental value, are widely distributed in diverse habitats and have complex taxonomy. Here 40 Gentiana chloroplast genomes were used for comparative genomic analysis and divergence time estimation. METHODS: The complete chloroplast genome of G. rhodantha was sequenced, assembled, and annotated. Comparative genomic and phylogenetic analysis were provided for variation analysis of Gentiana. RESULTS: Gentiana species satisfy the characteristics of intra-Sect conservation and inter-Sect variation in chloroplast genome structure and IR boundaries. All Gentiana Sects can be clustered into a single one and separated from each other; however, Ser. Apteroideae and Ser. Confertifoliae in Sect. Monopodiae are more closely related to Sect. Frigida and Sect. Cruciata, respectively. Gentiana has experienced two large gene loss events; the first, the collective loss of the rps16 gene at genus formation and the second, the collective loss of the ndh gene when Ser. Ornatae and Ser. Verticillatae completed their differentiation. Comparative genomic analysis support that Sect. Stenogyne and Sect. Otophora became the independent genera Metagentiana and Kuepferia. Seven divergence hotspot regions were screened based on Pi values, and could serve as DNA-specific barcodes for Gentiana. CONCLUSIONS: This study provides a further theoretical basis for taxonomic analysis, genetic diversity, evolutionary mechanism and molecular identification in Gentiana.


Assuntos
Genoma de Cloroplastos , Gentiana , Sequência de Bases , Genoma de Cloroplastos/genética , Genômica , Gentiana/genética , Filogenia
18.
ACS Nano ; 16(6): 8531-8539, 2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35704873

RESUMO

The efficiency of electrocatalytic reactions has been continuously improved in recent years due to the great effort in the development of electrocatalysts. A popular strategy is engineering the size of electrocatalysts for better electrochemical performance and lower cost. Nanosized electrocatalysts with high specific surface area have been widely used in state-of-the-art electrochemical devices such as fuel cells. From an engineering aspect, nanosizing electrocatalysts increases the surface area of the electrode and improves the electrode/device performance. Beyond an engineering scope, this perspective highlights the size effects of certain scientific fundamentals in electrocatalytic reactions. The paper summarizes the representative examples in studying the size effects of electrocatalysts and sheds light on the change of intrinsic properties of electrocatalysts caused by the size variation. The size effects of electrocatalysts should be investigated in terms of both engineering and fundamental aspects; that is, the observed activity change is more than a result of surface area variation, and it is interesting to investigate the link between the intrinsic activity and the properties of the catalysts.

19.
Eur J Med Chem ; 223: 113661, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34237636

RESUMO

Based on indole scaffold, a potent and selective phosphoinositide 3-kinase delta (PI3Kδ) inhibitor, namely FD223, was developed by the bioisosteric replacement drug discovery approach and studied for the treatment of acute myeloid leukemia (AML). In vitro studies revealed that FD223 displays high potency (IC50 = 1 nM) and selectivity (29-51 fold over other PI3K isoforms) against PI3Kδ, and exhibits efficient inhibition of the proliferation of AML cell lines (MOLM-16, HL-60, EOL-1 and KG-1) by suppressing p-AKT Ser473 thus causing G1 phase arrest during the cell cycle. Further given the favorable pharmacokinetic (PK) profiles of FD223, in vivo studies were evaluated using xenograft model in nude mice, confirming its significant antitumor efficacy meanwhile with no observable toxicity. All these results are comparable to the positive group of Idelalisib (CAL-101), indicating that FD223 has potential for further development as a promising PI3Kδ inhibitor for the treatment of leukemia such as AML.


Assuntos
Classe I de Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Desenho de Fármacos , Indóis/química , Inibidores de Fosfoinositídeo-3 Quinase/síntese química , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Meia-Vida , Humanos , Indóis/metabolismo , Indóis/farmacologia , Indóis/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/patologia , Camundongos , Camundongos Nus , Simulação de Acoplamento Molecular , Inibidores de Fosfoinositídeo-3 Quinase/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade , Transplante Heterólogo
20.
Bioorg Med Chem Lett ; 48: 128271, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34284105

RESUMO

Cinnoline is a potential pharmacophore which has rarely been reported for uses as PI3K inhibitors. In this study, a series of cinnoline derivatives were developed as PI3K inhibitors and evaluated for enzymatic and cellular activities. Most compounds displayed nanomolar inhibitory activities against PI3Ks, among which 25 displayed high LLE and micromolar inhibitory potency against three human tumor cell lines (IC50 = 0.264 µM, 2.04 µM, 1.14 µM).


Assuntos
Antineoplásicos/farmacologia , Descoberta de Drogas , Compostos Heterocíclicos com 2 Anéis/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Compostos Heterocíclicos com 2 Anéis/síntese química , Compostos Heterocíclicos com 2 Anéis/química , Humanos , Estrutura Molecular , Inibidores de Fosfoinositídeo-3 Quinase/síntese química , Inibidores de Fosfoinositídeo-3 Quinase/química , Relação Estrutura-Atividade
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