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1.
Br J Cancer ; 130(9): 1517-1528, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38459187

RESUMO

BACKGROUND: Circß-catenin, our first reported circRNA, has been reported to mediate tumorigenesis in various cancers. However, its biological functions and underlying mechanisms in colorectal cancer (CRC) remain unknown. METHODS: The qRT-PCR examination was used to detect the expression of circß-catenin, miR-197-3p, and CTNND1 in cells and human tissues. Western blot was conducted to detect the protein expression levels. The biological function of circß-catenin was verified by MTT, colony formation, wound healing, and transwell assays. The in vivo effects of circß-catenin were verified by nude mice xenograft and metastasis models. The regulatory network of circß-catenin/miR-197-3p/CTNND1 was confirmed via dual-luciferase reporter and RIP assays. RESULTS: In the present study, circß-catenin was found to promote CRC cell proliferation and metastasis in vitro and in vivo. Mechanistically, circß-catenin served as miRNA decoy to directly bind to miR-197-3p, then antagonized the repression of the target gene CTNND1, and eventually promoted the malignant phenotype of CRC. More interestingly, the inverted repeated Alu pairs termed AluJb1/2 and AluY facilitated the biogenesis of circß-catenin, which could be partially reversed by EIF4A3 binding to Alu element AluJb2. CONCLUSIONS: Our findings illustrated a novel mechanism of circß-catenin in modulating CRC tumorigenesis and metastasis, which provides a potential therapeutic target for CRC patients.


Assuntos
Proliferação de Células , Neoplasias Colorretais , Progressão da Doença , Fator de Iniciação 4A em Eucariotos , Camundongos Nus , MicroRNAs , RNA Circular , beta Catenina , MicroRNAs/genética , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , RNA Circular/genética , Animais , Camundongos , beta Catenina/metabolismo , beta Catenina/genética , Proliferação de Células/genética , Fator de Iniciação 4A em Eucariotos/genética , Fator de Iniciação 4A em Eucariotos/metabolismo , delta Catenina , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Masculino , Feminino , Movimento Celular/genética , Camundongos Endogâmicos BALB C
2.
Anal Chem ; 96(5): 2117-2123, 2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-38268109

RESUMO

Despite the progress that has been made in diverse DNA-based nanodevices to in situ monitor the activity of the DNA repair enzymes in living cells, the significance of improving both the sensitivity and specificity has remained largely neglected and understudied. Herein, we propose a regulatable DNA nanodevice to specifically monitor the activity of DNA repair enzymes for early evaluation of cancer mediated by genomic instability. Concretely, an AND logic gate-regulated DNAzyme nanoflower was rationally designed by the self-assembly of the DNA duplex modified with both apurinic/apyrimidinic (AP) site and methyl lesion site. The DNAzyme nanoflower could be reconfigured under the repair of AP sites and O6-methylguanine sites by apurinic/apyrimidinic endonuclease 1 (APE1) and O6-methylguanine methyltransferase (MGMT) to produce a fluorescent signal, realizing the sensitive monitoring of the activity of APE1 and MGMT. Compared to the free DNAzyme duplex, the fluorescent response of the DNAzyme nanoflower increased by 60%, due to the effective enrichment of the DNA probes by the nanoflower structure. More importantly, we have demonstrated that the dual-enzyme activated strategy allows imaging of specific cancer cells in the AND logic gate manner using MCF-7 as a cancer cell model, improving the specificity of cancer cell imaging. This AND logic gate-regulated multifunctional DNAzyme nanoflower provides a simple tool for simultaneously visualizing multiple DNA repair enzymes, holding great potential in early clinical diagnosis and drug discovery.


Assuntos
Reparo do DNA , DNA Catalítico , Dano ao DNA , Enzimas Reparadoras do DNA/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , DNA/química
3.
BMC Plant Biol ; 24(1): 152, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38418954

RESUMO

BACKGROUND: Due to being rooted in the ground, maize (Zea mays L.) is unable to actively escape the attacks of herbivorous insects such as the Asian corn borer (Ostrinia furnacalis). In contrast to the passive damage, plants have evolved defense mechanisms to protect themselves from herbivores. Salicylic acid, a widely present endogenous hormone in plants, has been found to play an important role in inducing plant resistance to insects. In this study, we screened and identified the insect resistance gene SPI, which is simultaneously induced by SA and O. furnacalis feeding, through preliminary transcriptome data analysis. The functional validation of SPI was carried out using bioinformatics, RT-qPCR, and heterologous expression protein feeding assays. RESULTS: Both SA and O. furnacalis treatment increased the expression abundance of SA-synthesis pathway genes and SPI in three maize strains, and the upregulation of SPI was observed strongly at 6 hours post-treatment. The expression of SPI showed a temporal relationship with SA pathway genes, indicating that SPI is a downstream defense gene regulated by SA. Protein feeding assays using two different expression vectors demonstrated that the variation in SPI protein activity among different strains is mainly due to protein modifications. CONCLUSIONS: Our research results indicate that SPI, as a downstream defense gene regulated by SA, is induced by SA and participates in maize's insect resistance. The differential expression levels of SPI gene and protein modifications among different maize strains are one of the reasons for the variation in insect resistance. This study provides new insights into ecological pest control in maize and valuable insights into plant responses to SA-induced insect resistance.


Assuntos
Mariposas , Zea mays , Animais , Zea mays/genética , Zea mays/metabolismo , Ácido Salicílico/farmacologia , Ácido Salicílico/metabolismo , Mariposas/genética , Insetos , Transcriptoma
4.
Small ; 20(29): e2400477, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38402438

RESUMO

Utilizing the ionic flux to generate voltage output has been confirmed as an effective way to meet the requirements of clean energy sources. Different from ionic thermoelectric (i-TE) and hydrovoltaic devices, a new hydrothermal chemical generator is designed by amorphous FeCl3 particles dispersing in MWCNT and unique ferric chloride or water gate. In the presence of gate, the special ion behaviors enable the cell to present a constant voltage of 0.60 V lasting for over 96 h without temperature difference. Combining the differences of cation concentration, humidity and temperature between the right and left side of sample, the maximum short-circuit current and power output can be obtained to 168.46 µA and 28.11 µW, respectively. The generator also can utilize the low-grade heat to produce electricity wherein Seebeck coefficient is 6.79 mV K-1. The emerged hydrothermal chemical generator offers a novel approach to utilize the low-grade heat, water and salt solution resources, which provides a simple, sustainable and low-cost strategy to realize energy supply.

5.
Small ; : e2307033, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38552219

RESUMO

Recently, aqueous zinc ion batteries (AZIBs) with the superior theoretical capacity, high safety, low prices, and environmental protection, have emerged as a contender for advanced energy storage. However, challenges related to cathode materials, such as dissolution, instability, and structural collapse, have hindered the progress of AZIBs. Here, a novel AZIB is constructed using an oxidized 2D layered MnBi2Te4 cathode for the first time. The oxidized MnBi2Te4 cathode with large interlayer spacing and low energy barrier for zinc ion diffusion at 240 °C, exhibited impressive characteristics, including a high reversibility capacity of 393.1 mAh g-1 (0.4 A g-1), outstanding rate performance, and long cycle stability. Moreover, the corresponding aqueous button cell also exhibits excellent electrochemical performance. To demonstrate the application in practice in the realm of flexible wearable electronics, a quasi-solid-state micro ZIB (MZIB) is constructed and shows excellent flexibility and high-temperature stability (the capacity does not significantly degrade when the temperature reaches 100 °C and the bending angle exceeds 150°). This research offers effective tactics for creating high-performance cathode materials for AZIBs.

6.
Small ; 20(13): e2305207, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37963824

RESUMO

2D perovskites have attracted tremendous attention due to their superior optoelectronic properties and potential applications in optoelectronic devices. Especially, the larger bandgap of 2D perovskite means that they are suitable for UV photodetection. However, the layered structure of 2D perovskites hinders the interlayer carrier transport, which limits the improvement of device performance. Therefore, nanoscale structures are normally used to enhance the light absorption ability, which is an effective strategy to improve the photocurrent in 2D perovskite-based photodetectors. Herein, a template-assisted low-temperature method is proposed to fabricate 2D perovskite ((C6H5C2H4NH3)2PbBr4, (PEA)2PbBr4) grating single crystal films (GSCFs). The crystallinity of the (PEA)2PbBr4 GSCFs is significantly improved due to the slow evaporation of the precursor solution under low temperatures. Based on this high crystalline quality and extremely ordered microstructures, the metal-semiconductor-metal photodetectors are assembled. Finite-different time-domain (FDTD) simulation and experiment indicate that the GSCF-based photodetectors exhibit significantly improved performance in comparison with the plane devices. The optimized 2D perovskite photodetectors are sensitive to UV light and demonstrate a responsivity and detectivity of 28.6 mA W-1 and 2.4 × 1011 Jones, respectively. Interestingly, the photocurrent of this photodetector varies as the angle of the incident polarized light, resulting in a high polarization ratio of 1.12.

7.
PLoS Pathog ; 18(9): e1010759, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36084159

RESUMO

Peste des petits ruminants virus (PPRV) is an important pathogen that seriously influences the productivity of small ruminants worldwide. PPRV is lymphotropic in nature and SLAM was identified as the primary receptor for PPRV and other Morbilliviruses. Many viruses have been demonstrated to engage extracellular vesicles (EVs) to facilitate their replication and pathogenesis. Here, we provide evidence that PPRV infection significantly induced the secretion levels of EVs from goat PBMC, and that PPRV-H protein carried in EVs can enhance SLAM receptor expression in the recipient cells via suppressing miR-218, a negative miRNA directly targeting SLAM gene. Importantly, EVs-mediated increased SLAM expression enhances PPRV infectivity as well as the expression of various cytokines related to SLAM signaling pathway in the recipient cells. Moreover, our data reveal that PPRV associate EVs rapidly entry into the recipient cells mainly through macropinocytosis pathway and cooperated with caveolin- and clathrin-mediated endocytosis. Taken together, our findings identify a new strategy by PPRV to enhance virus infection and escape innate immunity by engaging EVs pathway.


Assuntos
Vesículas Extracelulares , MicroRNAs , Peste dos Pequenos Ruminantes , Vírus da Peste dos Pequenos Ruminantes , Viroses , Animais , Caveolinas/metabolismo , Clatrina/metabolismo , Citocinas/metabolismo , Vesículas Extracelulares/metabolismo , Cabras/genética , Leucócitos Mononucleares , Ativação Linfocitária , MicroRNAs/genética , MicroRNAs/metabolismo , Vírus da Peste dos Pequenos Ruminantes/genética , Membro 1 da Família de Moléculas de Sinalização da Ativação Linfocitária/metabolismo
8.
Plant Physiol ; 194(1): 243-257, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-37399189

RESUMO

Plant lignocellulosic biomass, i.e. secondary cell walls of plants, is a vital alternative source for bioenergy. However, the acetylation of xylan in secondary cell walls impedes the conversion of biomass to biofuels. Previous studies have shown that REDUCED WALL ACETYLATION (RWA) proteins are directly involved in the acetylation of xylan but the regulatory mechanism of RWAs is not fully understood. In this study, we demonstrate that overexpression of a Populus trichocarpa PtRWA-C gene increases the level of xylan acetylation and increases the lignin content and S/G ratio, ultimately yielding poplar woody biomass with reduced saccharification efficiency. Furthermore, through gene coexpression network and expression quantitative trait loci (eQTL) analysis, we found that PtRWA-C was regulated not only by the secondary cell wall hierarchical regulatory network but also by an AP2 family transcription factor HARDY (HRD). Specifically, HRD activates PtRWA-C expression by directly binding to the PtRWA-C promoter, which is also the cis-eQTL for PtRWA-C. Taken together, our findings provide insights into the functional roles of PtRWA-C in xylan acetylation and consequently saccharification and shed light on synthetic biology approaches to manipulate this gene and alter cell wall properties. These findings have substantial implications for genetic engineering of woody species, which could be used as a sustainable source of biofuels, valuable biochemicals, and biomaterials.


Assuntos
Populus , Populus/genética , Populus/metabolismo , Xilanos/metabolismo , Acetilação , Biomassa , Biocombustíveis/análise , Plantas/metabolismo , Parede Celular/metabolismo , Lignina/metabolismo
9.
Biotechnol Bioeng ; 121(3): 799-822, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38079153

RESUMO

The chemical modifications (CMs) of protein is an important technique in chemical biology, protein-based therapy, and material science. In recent years, there has been rapid advances in the development of CMs of peptides and proteins, providing new approaches for peptide and protein functionalization, as well as drug discovery. In this review, we highlight the methods for chemically modifying tyrosine (Tyr) residues in different regions, offering a comprehensive exposition of the research content related to Tyr modification. This review summarizes and provides an outlook on Tyr residue modification, aiming to offer readers assistance in the site-selective modification of macromolecules and to facilitate application research in this field.


Assuntos
Peptídeos , Tirosina , Peptídeos/química
10.
J Org Chem ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38990146

RESUMO

A Mn-catalyzed ligand-directed Csp3-Csp2 coupling of tertiary allylic alcohols with arylaldehydes has been developed. The method provides an efficient approach to access 1,5-diarylpent-1-en-3-ones via carbon-skeleton rearrangement-based aldol reaction.

11.
J Org Chem ; 89(6): 3684-3695, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38394358

RESUMO

A Rh(III)-catalyzed oxidative 1,3-aryl migration of α-arylallylic alcohols via Csp2-Csp3 σ bond activation has been developed. This method provides an efficient strategy to allow for allylic alcohol-based skeleton rearrangement, in which various secondary and tertiary α-arylallylic alcohols are rapidly converted to ß-aryl-α, ß-unsaturated ketones and aldehydes.

12.
Inorg Chem ; 63(1): 39-43, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38133832

RESUMO

A novel zinc phosphate derivative of Sr2Be2B2O7 (SBBO), K(NH4)Zn2(PO4)2 (KNZP), featuring [Zn2P2O8]∞2- double layers akin to the [Be2B2O7]∞4- layers in SBBO, was successfully synthesized via a moderate hydrothermal method. Through the substitution of BeO4 and BO3 with ZnO4 and PO4, the issue of toxicity has been effectively resolved, while the enhanced interlayer interactions facilitated by covalent and hydrogen bonding in KNZP overcome the inherent structural instability. Notably, KNZP exhibits a wide transparent window and a moderate second-harmonic generation (SHG) intensity, reaching 0.7 times that of KH2PO4 (KDP), rendering it type-I phase-matchable, indicating that it is a promising UV nonlinear optical (NLO) material.

13.
Environ Sci Technol ; 58(6): 2902-2911, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38294202

RESUMO

Conventional biological nutrient removal processes rely on external aeration and produce significant carbon dioxide (CO2) emissions. This study constructed a phototrophic simultaneous nitrification-denitrification phosphorus removal (P-SNDPR) system to treat low carbon to nitrogen (C/N) ratios wastewater and investigated the impact of sludge retention time (SRT) on nutrient removal performance, nitrogen conversion pathway, and microbial structure. Results showed that the P-SNDPR system at SRT of 15 days had the highest nutrient removal capacity, achieving over 85% and 98% removal of nitrogen and phosphorus, respectively, meanwhile maintaining minimal CO2 emissions. Nitrogen removal was mainly through assimilation at SRTs of 5 and 10 days, and nitrification-denitrification at SRTs of 15 and 20 days. Stable partial nitrification was facilitated by photoinhibition and low DO levels. Flow cytometry sorting technique results revealed SRT drove community structural changes in translational activity (BONCAT+) microbes, where BONCAT+ microbes were mainly simultaneous nitrogen and phosphorus removal bacteria (Candidatus Accumulibacter), denitrifying bacteria (Candidatus Competibacter and Plasticicumulans), ammonia-oxidizing bacteria (Nitrosomonas), and microalgae (Chlorella and Dictyosphaerium). The P-SNDPR system represents a novel, carbon-neutral process for efficient nutrient removal from low C/N ratio wastewater without aeration and external carbon source additions.


Assuntos
Chlorella , Águas Residuárias , Nitrificação , Desnitrificação , Fósforo/metabolismo , Nitrogênio/química , Nitrogênio/metabolismo , Dióxido de Carbono , Chlorella/metabolismo , Eliminação de Resíduos Líquidos/métodos , Reatores Biológicos/microbiologia , Esgotos/microbiologia
14.
Thromb J ; 22(1): 25, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38475817

RESUMO

BACKGROUND: The retrieval of inferior vena cava (IVC) filter is essential for preventing complications associated with the device. Advanced techniques have been developed to improve the success rate of retrieving tip-embedded filters. The forceps technique is frequently used to address this issue. CASE PRESENTATION: We present a case study of two patients who underwent a successful tip-embedded IVC filter retrieval using a modified forceps technique, which has not been previously reported. This technique involves using a wire loop under the filter tip and a forceps to grasp the filter shoulder. By pulling the wire loop and pushing the forceps in counterforce, the filter tip is straightened and aligned with the vascular sheath. The vascular sheath can then dissect the filter tip out from the caval wall and get inside the sheath to complete the retrieval. CONCLUSIONS: The modified forceps technique we present here offers a new solution for the complex retrieval of IVC filters.

15.
Phys Chem Chem Phys ; 26(9): 7695-7705, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38372167

RESUMO

The determination of impact sensitivity of energetic materials traditionally relies on expensive and safety-challenged experimental means. This has instigated a shift towards scientific computations to gain insights into and predict the impact response of energetic materials. In this study, we refine the phonon-vibron coupling coefficients ζ in energetic materials subjected to impact loading, building upon the foundation of the phonon up-pumping model. Considering the full range of interactions between high-order phonon overtones and molecular vibrational frequencies, this is a pivotal element for accurately determining phonon-vibron coupling coefficients ζ. This new coupling coefficient ζ relies exclusively on phonon and molecular vibrational frequencies within the range of 0-700 cm-1. Following a regression analysis involving ζ and impact sensitivity (H50) of 45 molecular nitroexplosives, we reassessed the numerical values of damping factors, establishing a = 2.5 and b = 35. This coefficient is found to be a secondary factor in determining sensitivity, secondary to the rate of decomposition propagation and thermodynamic factor (heat of explosion). Furthermore, the relationship between phonon-vibron coupling coefficients ζ and impact sensitivity was studied in 16 energetic crystalline materials and eight nitrogen-rich energetic salts. It was observed that as the phonon-vibron coupling coefficient increases, the tendency for reduced impact sensitivity H50 still exists.

16.
J Phys Chem A ; 128(21): 4189-4198, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38748760

RESUMO

In order to investigate the impact of an external electric field on the sensitivity of ß-HMX explosives, we employ first-principles calculations to determine the molecular structure, dipole moment, and electronic properties of both ß-HMX crystals and individual ß-HMX molecules under varying electric fields. When the external electric field is increasing along the [100], [010], and [001] crystallographic directions of ß-HMX, the calculation results indicate that an increase in the bond length (N1-N3/N1'-N3') of the triggering bond, an increase in the main Qnitro (N3, N3') value, an increase in the minimum surface electrostatic potential, and a decrease in band gap all contribute to a reduction in its stability. Among these directions, the [010] direction exhibits the highest sensitivity, which can be attributed to the significantly smaller effective mass along the [010] direction compared with the [001] and [100] directions. Moreover, the application of an external electric field along the Y direction of the coordinate system on individual ß-HMX molecules reveals that the strong polarization effect induced by the electric field enhances the decomposition of the N1-N3 bonds. In addition, due to the periodic potential energy of ß-HXM crystal, the polarization effect of ß-HMX crystal caused by an external electric field is much smaller than that of a single ß-HXM molecule.

17.
Bioorg Chem ; 147: 107312, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38599053

RESUMO

A series of water-soluble PEGylated 1,2,4-triazoles 5-8 were successfully synthesized from methyl 5-(chloromethyl)-1-aryl-1H-1,2,4-triazole-3-carboxylates 1. All of the water-soluble PEGylated 1,2,4-triazoles were characterized by FT-IR and 1H NMR spectroscopy. The solubility, in vitro plasma stability, and anti-inflammatory activity were also determined and compared to original methyl 5-(halomethyl)-1-aryl-1H-1,2,4-triazole-3-carboxylates. For SAR study, all PEGylated 1,2,4-triazoles 5-8 performed potential anti-inflammatory activity on LPS-induced RAW 264.7 cells (IC50 = 3.42-7.81 µM). Moreover, the western blot result showed PEGylated 1,2,4-triazole 7d performed 5.43 and 2.37 folds inhibitory activity over iNOS and COX-2 expressions. On the other hand, the cell viability study revealed PEGylated 1,2,4-triazoles 7 and 8 with PEG molecular weight more than 600 presented better cell safety (cell viability > 95 %). Through the solubility and in vitro plasma stability studies, PEGylated 1,2,4-triazoles 7a-d exhibited higher hydrophilicity and prolonged 2.01 folds of half-life in compound 7d. Furthermore, the in vivo anti-inflammatory and gastric safety results indicated PEGylated 1,2,4-triazole 7d more effectively decreased the inflammatory response in edema and COX-2 expression and exhibited higher gastric safety than Indomethacin. Following the in vitro and in vivo study results, PEGylated 1,2,4-triazole 7d possessed favorable solubility, plasma stability features, safety, and significant anti-inflammatory activity to become the potential water-soluble anti-inflammatory candidate.


Assuntos
Polietilenoglicóis , Solubilidade , Triazóis , Água , Triazóis/química , Triazóis/farmacologia , Triazóis/síntese química , Animais , Camundongos , Água/química , Polietilenoglicóis/química , Relação Estrutura-Atividade , Edema/tratamento farmacológico , Edema/induzido quimicamente , Ciclo-Oxigenase 2/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células RAW 264.7 , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Estrutura Molecular , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Ratos , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Masculino , Relação Dose-Resposta a Droga , Carragenina
18.
Bioorg Chem ; 148: 107424, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38728908

RESUMO

Pyrazolopyrimidine derivatives, including pyrazolopyrimidines, 6-aminopyrazolopyrimidines, 6-[(formyloxy)methyl]pyrazolopyrimidines, 6-(hydroxymethyl)pyrazolopyrimidine, and 6-(aminomethyl)pyrazolopyrimidines have been successfully prepared and tested against NCI-H226, NPC-TW01, and Jurkat cancer cell lines. Among the tested pyrazolopyrimidine compounds, we found 6-aminopyrazolopyrimidines and 6-(aminomethyl)pyrazolopyrimidines with essential o-ClPh or p-ClPh substituted moieties on N-1 pyrazole ring exhibited the best IC50 inhibition activity for Jurkat cells. Furthermore, optimization of the SAR study on the C-6 position of pyrazolopyrimidine ring demonstrated that 6-(N-substituted-methyl)pyrazolopyrimidines 17b, 17d, and 19d possessed the significant IC50 inhibitory activity for the different leukemia cell lines, especially for Jurkat, K-562, and HL-60. On the other hand, further SAR inhibition and docking model studies revealed that compound 19d, which has a 3-(1H-imidazol-1-yl)propan-1-amino side-chain on the C-6 position, was able to form four hydrogen bonds with residues Ala226, Leu152, and Glu194 and specifically extended into the P1 pocket subsite with Aurora A, resulting in improved inhibitory activity almost similar to SNS-314. To explore the anti-cancer mechanism, compound 19d was measured by Western blot analysis in Jurkat T-cells, however, it showed non-responsibility to Aurora B. For the further structural modifications on the lateral chain of compound 19d, compounds 24 with longer lateral chain were designed and synthesized for testing leukemia cell lines. However, compounds 24 was significantly decrease inhibition potency against leukemia cell lines. Based on the in-vitro results, compounds 17b and 19d could be considered to be the best potential lead drug in our study for the development of new and effective therapies for leukemia treatment. On the other hand, the DHFR inhibition results indicated compound 19d possessed good inhibitory activity and better than the reported naphthalene derivative. Through further comparisons of the model superposition of three-dimensional (3D) conformations in DHFR, compound 19d presented a similar structural alignment to Methotrexate and the reported naphthalene derivative and led to similar drug-like functional relationships. As a results, compound 19d would be a potential DHFR inhibitor for anti-leukemia drug candidate.


Assuntos
Antineoplásicos , Proliferação de Células , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Pirazóis , Pirimidinas , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Pirimidinas/farmacologia , Pirimidinas/química , Pirimidinas/síntese química , Relação Estrutura-Atividade , Proliferação de Células/efeitos dos fármacos , Estrutura Molecular , Pirazóis/farmacologia , Pirazóis/química , Pirazóis/síntese química , Simulação de Acoplamento Molecular , Relação Dose-Resposta a Droga , Linhagem Celular Tumoral , Leucemia/tratamento farmacológico , Leucemia/patologia , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química
19.
Mol Divers ; 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38229000

RESUMO

A series of flavonol derivatives containing benzoxazole were designed and synthesized, and the structures of all the target compounds were determined by nuclear magnetic resonance (NMR) and high-resolution mass spectrometry (HRMS). The structure of X2 was further confirmed by single crystal X-ray diffraction analysis. The results of the bioactivity tests showed that some of the target compounds possessed excellent antiviral activity against tobacco mosaic virus (TMV) in vivo. In particular, the median effective concentration (EC50) values for the curative and protective activities of X17 against TMV were 127.6 and 101.2 µg/mL, respectively, which were superior to those of ningnanmycin (320.0 and 234.6 µg/mL). The results of preliminary mechanism study indicated that X17 had a strong binding affinity for TMV coat protein (TMV-CP), which might hinder the self-assembly and replication of TMV particles. In addition, X17 was able to effectively inhibit tobacco leaf membrane lipid peroxidation and facilitate the removal of O2- from the body, thereby improving the disease resistance of tobacco plants. Therefore, the design and synthesis of flavonol derivatives containing benzoxazole provides value for the development of new antiviral drugs.

20.
J Chem Phys ; 160(2)2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38205850

RESUMO

Doubly resonant sum frequency generation (DR-SFG) serves as a potent characteristic technique for probing the electronic spectra and vibronic coupling of molecules on surfaces. In this study, we successfully developed a novel infrared (IR)-white light (WL) DR-SFG spectroscopy based on narrowband IR and tunable broadband WL. This novel method was employed to explore the excitation spectrum and vibronic couplings of sub-monolayer Rhodamine 6G molecules. Our findings elucidate that the xanthene skeleton vibrational modes exhibit strong coupling with the S0-S1 electronic transition. Notably, we observed not only the 0-0 transition of the S0-S1 electronic continuum but also the 0-1 transition, a first time observation in the realm of DR-SFG spectroscopy. This advanced DR-SFG spectroscopy methodology facilitates a more sensitive examination of electronic spectra and the coupling between electronic transitions and vibrational modes, heralding a significant advancement in the understanding of molecular interactions on surfaces.

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