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1.
Cell Res ; 34(8): 545-555, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38834762

RESUMO

Coupling distinct enzymatic effectors emerges as an efficient strategy for defense against phage infection in bacterial immune responses, such as the widely studied nuclease and cyclase activities in the type III CRISPR-Cas system. However, concerted enzymatic activities in other bacterial defense systems are poorly understood. Here, we biochemically and structurally characterize a two-component defense system DUF4297-HerA, demonstrating that DUF4297-HerA confers resistance against phage infection by cooperatively cleaving dsDNA and hydrolyzing ATP. DUF4297 alone forms a dimer, and HerA alone exists as a nonplanar split spiral hexamer, both of which exhibit extremely low enzymatic activity. Interestingly, DUF4297 and HerA assemble into an approximately 1 MDa supramolecular complex, where two layers of DUF4297 (6 DUF4297 molecules per layer) linked via inter-layer dimerization of neighboring DUF4297 molecules are stacked on top of the HerA hexamer. Importantly, the complex assembly promotes dimerization of DUF4297 molecules in the upper layer and enables a transition of HerA from a nonplanar hexamer to a planar hexamer, thus activating their respective enzymatic activities to abrogate phage infection. Together, our findings not only characterize a novel dual-enzyme anti-phage defense system, but also reveal a unique activation mechanism by cooperative complex assembly in bacterial immunity.


Assuntos
Bacteriófagos , Bacteriófagos/enzimologia , Adenosina Trifosfatases/metabolismo , Adenosina Trifosfatases/química , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Sistemas CRISPR-Cas , Multimerização Proteica , Trifosfato de Adenosina/metabolismo , Modelos Moleculares
2.
J Pharm Pharmacol ; 76(9): 1079-1114, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-38687135

RESUMO

OBJECTIVES: Oxytropis DC is a perennial plant of Fabaceae family, which is widely distributed in the northern temperate zone. It is known as "locoweed" because of its toxic component swainsonine. However, it is widely used in Tibetan medicine and Mongolian medicine, mainly for the treatment of heat-clearing and detoxifying, pain-relieving, anti-inflammatory, hemostasis, and other diseases. To provide a basis for the further development and utilization of Oxytropis DC, the pieces of literature about the application, phytochemistry, pharmacological action, and toxicity of Oxytropis DC were reviewed and analyzed. KEY FINDINGS: A total of 373 chemical constituents were found from Oxytropis DC, including flavonoids, alkaloids, steroids, terpenoids, and others. Pharmacological actions mainly include antitumor, antioxidation, anti-inflammatory, analgesic, antibacterial, antifibrosis, and other pharmacological actions, among them, the antitumor effect is particularly prominent. SUMMARY: At present, studies on its pharmacological effects are mainly concentrated on the extracts, some flavonoids, and alkaloids. In the follow-up studies, research on the pharmacological activities of the other chemical constituents in Oxytropis should be strengthened. It has the potential to pave the way for research and development of novel Oxytropis medicines.


Assuntos
Oxytropis , Extratos Vegetais , Oxytropis/química , Humanos , Animais , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Flavonoides/farmacologia , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/isolamento & purificação , Alcaloides/farmacologia , Alcaloides/química , Fitoterapia , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Antineoplásicos Fitogênicos/farmacologia
3.
Sci Adv ; 10(16): eadk1855, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38630814

RESUMO

Transfected stem cells and T cells are promising in personalized cell therapy and immunotherapy against various diseases. However, existing transfection techniques face a fundamental trade-off between transfection efficiency and cell viability; achieving both simultaneously remains a substantial challenge. This study presents an acoustothermal transfection method that leverages acoustic and thermal effects on cells to enhance the permeability of both the cell membrane and nuclear envelope to achieve safe, efficient, and high-throughput transfection of primary T cells and stem cells. With this method, two types of plasmids were simultaneously delivered into the nuclei of mesenchymal stem cells (MSCs) with efficiencies of 89.6 ± 1.2%. CXCR4-transfected MSCs could efficiently target cerebral ischemia sites in vivo and reduce the infarct volume in mice. Our acoustothermal transfection method addresses a key bottleneck in balancing the transfection efficiency and cell viability, which can become a powerful tool in the future for cellular and gene therapies.


Assuntos
Células-Tronco Mesenquimais , Camundongos , Animais , Transfecção , Células-Tronco Mesenquimais/metabolismo , Plasmídeos , Membrana Celular , Terapia Baseada em Transplante de Células e Tecidos
4.
Artigo em Inglês | MEDLINE | ID: mdl-37874471

RESUMO

This study investigated the chemical and volatile characteristics of sea buckthorn fruits from three different regions in China. The chemical composition of the volatile oil was determined by using a non-targeted gas chromatography and mass spectrometry (GC/MS) method and the differences in chemical composition among the three producing areas were compared by heatmap providing a visual basis for researchers. A total of 93 compounds were identified, including 52 compounds from the Northeast China, 51 from the Xinjiang region, and 37 from Inner Mongolia region. Then, the in vitro antioxidant activity of sea buckthorn fruit oil was measured using DPPH, ABTS, and SOD inhibition tests, and the results showed that sea buckthorn fruit oil in northeast China was the strongest antioxidant, followed by Inner Mongolia and Xinjiang. The results of the CCK-8 experiment indicated that within the tested concentration, there is no cell cytotoxicity of the essential oil in human umbilical vein endothelial cells (HUVECs) cells. The results could supply reference to distinguish sea buckthorn fruit from different production areas and, meanwhile, clarify the activity and safety of sea buckthorn oil.

5.
Chem Biol Drug Des ; 102(3): 444-456, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36509697

RESUMO

The natural products plinabulin, docetaxel, and vinblastine are microtubule targeting agents (MTAs). They have been used alone or in combination in cancer treatment. However, the exact nature of their effects on microtubule (MT) polymerization dynamics is poorly understood. To elucidate the longitudinal conformational and energetic changes during MT dynamics, a total of 140 ns molecular dynamic simulations combined with binding free energy calculations were performed on seven tubulin models. The results indicated that the drugs disrupted MT polymerization by altering both MT conformation and binding free energy of the neighboring tubulin subunits. The combination of plinabulin and docetaxel destabilized MT polymerization due to bending MT and weakening the polarity of tubulin polymerization. The new combination of docetaxel and vinblastine synergistically enhanced MT depolymerization and bending, while plinabulin and vinblastine had no synergistic inhibitory effects. The results were verified by the tubulin assembly assay. Our study obtained a comprehensive understanding of the action mechanisms of three natural drugs and their combinations on MT dynamic, provided theoretical guidance for new MTA combinations, and would promote the optimal use of MTA and contribute to developing new MTAs as anticancer agents.


Assuntos
Antineoplásicos , Moduladores de Tubulina , Tubulina (Proteína) , Antineoplásicos/farmacologia , Docetaxel/farmacologia , Docetaxel/metabolismo , Microtúbulos , Tubulina (Proteína)/metabolismo , Vimblastina/farmacologia , Vimblastina/análise , Vimblastina/metabolismo , Moduladores de Tubulina/química , Moduladores de Tubulina/farmacologia
6.
Pharmaceuticals (Basel) ; 15(12)2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36559019

RESUMO

Cydonia Oblonga Mill. is widely distributed in Turkey, Uzbekistan and China and commonly used by the food industry to produce jam, jelly and candies. The aim of this study was to investigate the in vitro antidiabetic activity and anti-diabetic mechanism of Cydonia Oblonga Mill. fruit (COMF). The chemical compositions were further characterized in COMF by UPLC-Q-Orbitrap/MS and 65 components including 22 flavonoids, 16 organic acids, 11 polyphenols, 5 amino acids, 3 pentacyclic triterpenoids and 8 other compounds were identified. The antioxidant activity by DPPH scavenging method and α-glucosidase inhibitory activity were tested. Furthermore, we detected the effects of COMF extract on the proliferation activity of HUVECs, cell viability of HUVECs under H2O2-induced oxidative stress, and NO production. Then, molecular docking activity and α-glucosidase inhibitory activity of seven key flavonoid components selected by bioinformatics analysis and literature in the COMF were studied. Among them, quercetin showed potent inhibitory activity, kaempferol, isorhamnetin, luteolin and apigenin demonstrated moderate inhibitory activity, while rutin and epicatechin exhibited poor inhibitory activity. Subsequently, the effects of quercetin, kaempferol, isorhamnetin, leteolin and apigenin on the gene expression levels of AKT1, IL-6 and VEGFA were verified by real-time fluorescence quantification (RT-qPCR). Molecular biology result showed that different active ingredients can significantly recover the levels of AKT1, IL-6 and VEGFA in HUVECs injured by high glucose.

7.
J Oncol ; 2022: 2306451, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35528242

RESUMO

Due to the greater prevalence of chronic hepatitis B infection, liver tumor is especially popular in China. In China, it is the 4th most prevalent tumor and the 3rd main reason for cancer fatalities. Hepatocellular carcinomas (HCCs) account for more than 91% of every liver tumor case, and chemotherapy and immunotherapy are the better therapy choices. It is a serious threat to the lives and health of Chinese citizens. Patients diagnosed with liver tumors have a bad prognosis. Surgical resection, liver transplantation, chemotherapeutic embolization, and radiofrequency ablation (RFA) are all choices for patients who are detected early. More effective therapies can result in a better prognosis. This paper analyzes the clinical efficiency of interventional transarterial chemoembolization (TACE) integrated with monopolar radiofrequency ablation (RFA) on patients with a liver tumor. Initially, the dataset is collected and the patients are treated with combined TACE and RFA. The computed tomography (CT) images are obtained using three-phase CT imaging. The images are segmented using adaptive U-Net-based segmentation. The clinical efficiency of the patients is evaluated using Robust Residual Convolutional Neural Network (RR-CNN) which is optimized using Firefly Particle Swarm Optimization (FPSO) algorithm. The performance of the system is analyzed using the MATLAB simulation tool. In performance analysis, the proposed method of RR-CNN is high when compared to the existing method of CNN, logistic regression using genetic algorithm and KNN in overall parameters are accuracy, sensitivity, F1-score, and specificity. These integrated treatments have a suggested greater response frequency, indicating a synergistic impact by combination treatment in the initial stages.

8.
Adv Mater Technol ; 7(1)2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35399914

RESUMO

A surge of research in intracellular delivery technologies is underway with the increased innovations in cell-based therapies and cell reprogramming. Particularly, physical cell membrane permeabilization techniques are highlighted as the leading technologies because of their unique features, including versatility, independence of cargo properties, and high-throughput delivery that is critical for providing the desired cell quantity for cell-based therapies. Amongst the physical permeabilization methods, sonoporation holds great promise and has been demonstrated for delivering a variety of functional cargos, such as biomolecular drugs, proteins, and plasmids, to various cells including cancer, immune, and stem cells. However, traditional bubble-based sonoporation methods usually require special contrast agents. Bubble-based sonoporation methods also have high chances of inducing irreversible damage to critical cell components, lowering the cell viability, and reducing the effectiveness of delivered cargos. To overcome these limitations, several novel non-bubble-based sonoporation mechanisms are under development. This review will cover both the bubble-based and non-bubble-based sonoporation mechanisms being employed for intracellular delivery, the technologies being investigated to overcome the limitations of traditional platforms, as well as perspectives on the future sonoporation mechanisms, technologies, and applications.

9.
Nat Mater ; 21(5): 540-546, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35332292

RESUMO

Precise and selective manipulation of colloids and biological cells has long been motivated by applications in materials science, physics and the life sciences. Here we introduce our harmonic acoustics for a non-contact, dynamic, selective (HANDS) particle manipulation platform, which enables the reversible assembly of colloidal crystals or cells via the modulation of acoustic trapping positions with subwavelength resolution. We compose Fourier-synthesized harmonic waves to create soft acoustic lattices and colloidal crystals without using surface treatment or modifying their material properties. We have achieved active control of the lattice constant to dynamically modulate the interparticle distance in a high-throughput (>100 pairs), precise, selective and reversible manner. Furthermore, we apply this HANDS platform to quantify the intercellular adhesion forces among various cancer cell lines. Our biocompatible HANDS platform provides a highly versatile particle manipulation method that can handle soft matter and measure the interaction forces between living cells with high sensitivity.


Assuntos
Acústica , Coloides , Coloides/química , Ciência dos Materiais
10.
Microsyst Nanoeng ; 7: 63, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34567775

RESUMO

Exosomes are cell-derived nanovesicles that have recently gained popularity as potential biomarkers in liquid biopsies due to the large amounts of molecular cargo they carry, such as nucleic acids and proteins. However, most existing exosome-based analytical sensing methods struggle to achieve high sensitivity and high selectivity simultaneously. In this work, we present an electrochemical micro-aptasensor for the highly sensitive detection of exosomes by integrating a micropatterned electrochemical aptasensor and a hybridization chain reaction (HCR) signal amplification method. Specifically, exosomes are enriched on CD63 aptamer-functionalized electrodes and then recognized by HCR products with avidin-horseradish peroxidase (HRP) attached using EpCAM aptamers as bridges. Subsequently, the current signal that is generated through the enzyme reaction between the HRP enzyme and 3,3',5,5'-tetramethylbenzidine (TMB)/H2O2 directly correlates to the amount of bound HRP on the HCR products and thus to the number of target exosomes. By introducing anti-EpCAM aptamers, micro-aptasensors can detect cancerous exosomes with high specificity. Due to the micropatterned electrodes and HCR dual-amplification strategy, the micro-aptasensors achieve a linear detection response for a wide range of exosome concentrations from 2.5×103 to 1×107 exosomes/mL, with a detection limit of 5×102 exosomes/mL. Moreover, our method successfully detects lung cancer exosomes in serum samples of early-stage and late-stage lung cancer patients, showcasing the great potential for early cancer diagnosis.

11.
Nutr Metab (Lond) ; 18(1): 53, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34039393

RESUMO

BACKGROUND: Soybean oil is a very common edible oil in daily life. With the changes in the dietary composition, the intake of soybean oil increased. However, the effects of dietary intake of soybean oil on testosterone production are still unclear. METHODS: In order to study the effects of increasing intake of soybean oil on the synthesis of testosterone in Leydig cells, we fed male C57BL/6 mice on the diet which added 20% soybean salad oil (SOY group). We detected the hormone levels by enzyme-linked immunosorbent assay (ELISA) kits and serum fatty acid composition by gas chromatography, and analyzed the expression of steroidogenic enzymes by Real-Time PCR or immunoblotting analysis. RESULTS: After the 16-week feeding period, serum linoleic acid (LA) and α-linolenic acid (ALA) significantly increased and serum palmitic acid (PA) significantly decreased in SOY group mice. Compared to the normal diet (ND group), increasing intake of soybean oil raised the luteinizing hormone (LH) levels and up-regulated luteinizing hormone/chorionic gonadotropin receptor (LHCGR), steroidogenic acute regulatory protein (StAR) and cytochrome P450 family 11 subfamily A member I (CYP11A1). Testosterone levels in SOY group were higher than that in the ND group, and significantly difference showed. CONCLUSIONS: Increasing intake of soybean oil could raise the serum LA and ALA levels and decrease serum PA levels. This could activate the LH/LHCGR pathway and improve the function of steroid synthesis in Leydig cells, and finally lead to the elevated testosterone levels.

12.
Proc Natl Acad Sci U S A ; 117(20): 10976-10982, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32358194

RESUMO

Advances in gene editing are leading to new medical interventions where patients' own cells are used for stem cell therapies and immunotherapies. One of the key limitations to translating these treatments to the clinic is the need for scalable technologies for engineering cells efficiently and safely. Toward this goal, microfluidic strategies to induce membrane pores and permeability have emerged as promising techniques to deliver biomolecular cargo into cells. As these technologies continue to mature, there is a need to achieve efficient, safe, nontoxic, fast, and economical processing of clinically relevant cell types. We demonstrate an acoustofluidic sonoporation method to deliver plasmids to immortalized and primary human cell types, based on pore formation and permeabilization of cell membranes with acoustic waves. This acoustofluidic-mediated approach achieves fast and efficient intracellular delivery of an enhanced green fluorescent protein-expressing plasmid to cells at a scalable throughput of 200,000 cells/min in a single channel. Analyses of intracellular delivery and nuclear membrane rupture revealed mechanisms underlying acoustofluidic delivery and successful gene expression. Our studies show that acoustofluidic technologies are promising platforms for gene delivery and a useful tool for investigating membrane repair.


Assuntos
Técnicas de Transferência de Genes , Terapia Genética/métodos , Transplante de Células-Tronco Hematopoéticas/métodos , Sistema Hematopoético , Células-Tronco , Sobrevivência Celular , Citoplasma , Expressão Gênica , Técnicas de Transferência de Genes/instrumentação , Terapia Genética/instrumentação , Proteínas de Fluorescência Verde/genética , Humanos , Células Jurkat , Plasmídeos , Som
13.
Horm Metab Res ; 52(10): 712-717, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32365399

RESUMO

Although subacute thyroiditis (SAT) is thought to be a self-limited inflammatory thyroid disease, the recurrence rate of SAT is approximately 10-20%. It is difficult for these patients to stop glucocorticoid treatment, and they are usually bothered with recurrent pain and the side effects of glucocorticoids for more than several months. We describe three cases who were diagnosed with recurrent subacute thyroiditis after a reduction in prednisolone (PSL) dose, either immediately upon the cessation of PSL or shortly thereafter. Their symptoms, including the adverse effects of PSL, severely impacted their quality of life. After a complete assessment, we administered colchicine at 1 mg per day for 1-2 months to control the recurrence of SAT and monitored their routine blood parameters every two weeks. All 3 patients were successfully tapered off of PSL treatment and were free of frequently recurrent SAT. Colchicine may be therapeutic in patients with prednisolone-refractory, recurrent SAT. However, a large-scale, double-blind, controlled, prospective multicenter study is required to provide a solid body of evidence.


Assuntos
Colchicina/uso terapêutico , Resistência a Medicamentos/efeitos dos fármacos , Glucocorticoides/uso terapêutico , Supressores da Gota/uso terapêutico , Terapia de Salvação , Tireoidite Subaguda/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Recidiva , Tireoidite Subaguda/patologia
14.
Lab Chip ; 20(7): 1298-1308, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32195522

RESUMO

Separation of nano/microparticles based on surface acoustic waves (SAWs) has shown great promise for biological, chemical, and medical applications ranging from sample purification to cancer diagnosis. However, the permanent bonding of a microchannel onto relatively expensive piezoelectric substrates and excitation transducers renders the SAW separation devices non-disposable. This limitation not only requires cumbersome cleaning and increased labor and material costs, but also leads to cross-contamination, preventing their implementation in many biological, chemical, and medical applications. Here, we demonstrate a high-performance, disposable acoustofluidic platform for nano/microparticle separation. Leveraging unidirectional interdigital transducers (IDTs), a hybrid channel design with hard/soft materials, and tilted-angle standing SAWs (taSSAWs), our disposable acoustofluidic devices achieve acoustic radiation forces comparable to those generated by existing permanently bonded, non-disposable devices. Our disposable devices can separate not only microparticles but also nanoparticles. Moreover, they can differentiate bacteria from human red blood cells (RBCs) with a purity of up to 96%. Altogether, we developed a unidirectional IDT-based, disposable acoustofluidic platform for micro/nanoparticle separation that can achieve high separation efficiency, versatility, and biocompatibility.


Assuntos
Acústica , Som , Humanos , Dispositivos Lab-On-A-Chip , Transdutores
15.
Lab Chip ; 20(7): 1281-1289, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32154525

RESUMO

Manipulation of microparticles and bio-samples is a critical task in many research and clinical settings. Recently, acoustic based methods have garnered significant attention due to their relatively simple designs, and biocompatible and precise manipulation of small objects. Herein, we introduce a flexural wave based acoustofluidic manipulation platform that utilizes low-frequency (4-6 kHz) commercial buzzers to achieve dynamic particle concentration and translation in an open fluid well. The device has two primary modes of functionality, wherein particles can be concentrated in pressure nodes that are present on the bottom surface of the device, or particles can be trapped and manipulated in streaming vortices within the fluid domain; both of these functions result from flexural mode vibrations that travel from the transducers throughout the device. Throughout our research, we numerically and experimentally explored the wave patterns generated within the device, investigated the particle concentration phenomenon, and utilized a phase difference between the two transducers to achieve precision movement of fluid vortices and the entrapped particle clusters. With its simple, low-cost nature and open fluidic chamber design, this platform can be useful in many biological, biochemical, and biomedical applications, such as tumor spheroid generation and culture, as well as the manipulation of embryos.


Assuntos
Acústica , Som , Transdutores , Vibração
16.
Bioorg Med Chem ; 26(8): 2061-2072, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29571653

RESUMO

Based on the co-crystal structures of tubulin with plinabulin and Compound 1 (a derivative of plinabulin), a total of 18 novel plinabulin derivatives were designed and synthesized. Their biological activities were evaluated against human pancreatic cancer BxPC-3 cell lines. Two novel Compounds 13d and 13e exhibited potent activities with IC50 at 1.56 and 1.72 nM, respectively. The tubulin polymerization assay indicated that these derivatives could inhibit microtubule polymerization. Furthermore, the interaction between tubulin and these compounds were elucidated by molecular docking. The binding modes of Compounds 13d and 13e were similar to the co-crystal structure of Compound 1. H-π interaction was observed between the aromatic hydrogen of thiophene moiety with Phe20, which could enhance their binding affinities.


Assuntos
Antineoplásicos/síntese química , Dicetopiperazinas/química , Desenho de Fármacos , Moduladores de Tubulina/síntese química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Dicetopiperazinas/metabolismo , Dicetopiperazinas/farmacologia , Humanos , Simulação de Acoplamento Molecular , Neoplasias Pancreáticas/patologia , Estrutura Terciária de Proteína , Solubilidade , Relação Estrutura-Atividade , Tubulina (Proteína)/química , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/metabolismo , Moduladores de Tubulina/farmacologia
17.
RSC Adv ; 8(2): 1055-1064, 2018 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-35538960

RESUMO

Microtubules are a favorable target for development of anticancer agents. In this study, the anti-proliferative activities of plinabulin and six diketopiperazine derivatives were evaluated against human lung cancer cell line NCI-H460 and human pancreatic cancer cell line BxPC-3. The inhibition activities on these microtubules were assessed by tubulin polymerization and immunofluorescence assays. To gain insight into the interaction mechanism of the derivatives and tubulin, a molecular dynamics simulation was performed. We discovered that the diketopiperazine derivatives could prevent tubulin assembly through conformational changes. Molecular Mechanics/Poisson-Boltzmann Surface Area (MM-PBSA) calculations showed that the trend of the binding free energies of these inhibitors was in agreement with the trend of their biological activities. Introducing hydrophobic groups into the A-ring was favorable for binding. Energy decomposition indicated that van der Waals interaction played an essential role in the binding affinity of tubulin polymerization inhibitors. In addition, the key residues responsible for inhibitor binding were identified. In summary, this study provided valuable information for development of novel tubulin polymerization inhibitors as anticancer agents.

18.
Chem Biol Drug Des ; 90(4): 609-617, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28338292

RESUMO

A series of novel indazole-based diarylurea derivatives targeting c-kit were designed by structure-based drug design. The derivatives were prepared, and their antiproliferative activities were evaluated against human colon cancer HCT-116 cell line and hepatocellular carcinoma PLC/PRF/5 cell line. The antiproliferative activities demonstrated that six of nine compounds exhibited comparable activities with sorafenib against HCT-116. The structure-activity relationship (SAR) analysis indicated that the indazole ring part tolerated different kinds of substituents, and the N position of the central pyridine ring played key roles in antiproliferative activity. The SAR and interaction mechanisms were further explored using molecular docking method. Compound 1i with N-(2-(pyrrolidin-1-yl)ethyl)-carboxamide possessed improved solubility, 596.1 ng/ml and best activities, IC50 at 1.0 µm against HCT-116, and 3.48 µm against PLC/PRF/5. It is a promising anticancer agent for further development.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Indazóis/química , Indazóis/farmacologia , Ureia/análogos & derivados , Ureia/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desenho Assistido por Computador , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Células HCT116 , Humanos , Simulação de Acoplamento Molecular , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Niacinamida/análogos & derivados , Niacinamida/farmacologia , Compostos de Fenilureia/farmacologia , Proteínas Proto-Oncogênicas c-kit/metabolismo , Sorafenibe , Relação Estrutura-Atividade
19.
Nat Chem Biol ; 11(9): 625-31, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26284661
20.
Ultrasonics ; 62: 203-12, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26049731

RESUMO

Guided wavefield analysis methods for detection and quantification of crack damage in an aluminum plate are presented in this paper. New wavenumber components created by abrupt wave changes at the structural discontinuity are identified in the frequency-wavenumber spectra. It is shown that the new wavenumbers can be used to detect and characterize the crack dimensions. Two imaging based approaches, filter reconstructed imaging and spatial wavenumber imaging, are used to demonstrate how the cracks can be evaluated with wavenumber analysis. The filter reconstructed imaging is shown to be a rapid method to map the plate and any existing damage, but with less precision in estimating crack dimensions; while the spatial wavenumber imaging provides an intensity image of spatial wavenumber values with enhanced resolution of crack dimensions. These techniques are applied to simulated wavefield data, and the simulation based studies show that spatial wavenumber imaging method is able to distinguish cracks of different severities. Laboratory experimental validation is performed for a single crack case to confirm the methods' capabilities for imaging cracks in plates.

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