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1.
Biochem Biophys Res Commun ; 591: 118-123, 2022 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-35007835

RESUMEN

3-chyomotrypsin like protease (3CLpro) has been considered as a promising target for developing anti-SARS-CoV-2 drugs. Herein, about 6000 compounds were analyzed by high-throughput screening using enzyme activity model, and Merbromin, an antibacterial agent, was identified as a potent inhibitor of 3CLpro. Merbromin strongly inhibited the proteolytic activity of 3CLpro but not the other three proteases Proteinase K, Trypsin and Papain. Michaelis-Menten kinetic analysis showed that Merbromin was a mixed-type inhibitor of 3CLpro, due to its ability of increasing the KM and decreasing the Kcat of 3CLpro. The binding assays and molecular docking suggested that 3CLpro possessed two binding sites for Merbromin. Consistently, Merbromin showed a weak binding to the other three proteases. Together, these findings demonstrated that Merbromin is a selective inhibitor of 3CLpro and provided a scaffold to design effective inhibitors of SARS-CoV-2.


Asunto(s)
Proteasas 3C de Coronavirus/antagonistas & inhibidores , Merbromina/farmacología , Simulación del Acoplamiento Molecular , Inhibidores de Proteasas/farmacología , SARS-CoV-2/efectos de los fármacos , Sitios de Unión , COVID-19/prevención & control , COVID-19/virología , Proteasas 3C de Coronavirus/química , Proteasas 3C de Coronavirus/metabolismo , Ensayos Analíticos de Alto Rendimiento/métodos , Humanos , Cinética , Merbromina/química , Merbromina/metabolismo , Modelos Moleculares , Estructura Molecular , Inhibidores de Proteasas/química , Inhibidores de Proteasas/metabolismo , Unión Proteica , Dominios Proteicos , SARS-CoV-2/enzimología , SARS-CoV-2/fisiología , Resonancia por Plasmón de Superficie/métodos
2.
Bioorg Med Chem Lett ; 38: 127859, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33609662

RESUMEN

A pair of undescribed enantiomers, (±) ficusflavonid A (1a/1b), along with five known analogues, were isolated from the roots of Ficus hirta. Their structures were determined by the analysis of extensive spectroscopic data (including UV, IR, HRESIMS and NMR). Two enantiomers (1a and 1b) were successfully separated by chiral chromatographic column and their absolute configurations were assigned by the comparison of experimental and calculated ECD data. The cytotoxicity of all the isolates against HeLa, MCF-7, HepG2 and H460 cell lines were evaluated by MTT assay. Among them, 4 suppressed the proliferation of HeLa cells with the IC50 value of 28.88 µM. Furthermore, the apoptotic effect of 4 on HeLa cells and the level of several crucial proteins in AKT/MAPKs signaling pathways were analyzed by flow cytometer and western blot assay. As a result, 4 induced HeLa cell apoptosis in a dose dependent manner and significantly increased the protein levels of p-JNK and p-p38, whereas distinctly reduced the expression of p-AKT, and p-ERK. Thus, compound 4 might induce HeLa cells apoptosis via MAPK and AKT signaling pathways, which could be considered as a potential leading compound for the development of anticancer drugs.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Ficus/química , Flavonoides/farmacología , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Flavonoides/síntesis química , Flavonoides/química , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Estructura Molecular , Proteínas Proto-Oncogénicas c-akt/metabolismo , Relación Estructura-Actividad
3.
Sensors (Basel) ; 21(13)2021 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-34199118

RESUMEN

This paper proposes an optimized trajectory planner and motion planner framework, which aim to deal with obstacle avoidance along a reference road for autonomous driving in unstructured environments. The trajectory planning problem is decomposed into lateral and longitudinal planning sub-tasks along the reference road. First, a vehicle kinematic model with road coordinates is established to describe the lateral movement of the vehicle. Then, nonlinear optimization based on a vehicle kinematic model in the space domain is employed to smooth the reference road. Second, a multilayered search algorithm is applied in the lateral-space domain to deal with obstacles and find a suitable path boundary. Then, the optimized path planner calculates the optimal path by considering the distance to the reference road and the curvature constraints. Furthermore, the optimized speed planner takes into account the speed boundary in the space domain and the constraints on vehicle acceleration. The optimal speed profile is obtained by using a numerical optimization method. Furthermore, a motion controller based on a kinematic error model is proposed to follow the desired trajectory. Finally, the experimental results show the effectiveness of the proposed trajectory planner and motion controller framework in handling typical scenarios and avoiding obstacles safely and smoothly on the reference road and in unstructured environments.

4.
Mar Drugs ; 18(7)2020 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-32708154

RESUMEN

12-Deacetyl-12-epi-scalaradial, a scalarane sesterterpenoid from a marine sponge Hippospongia sp, has been reported to possess cytotoxic activity on HepG2, MCF-7, and HCT-116 cells. However, there is no research to indicate that 12-deacetyl-12-epi-scalaradial exhibited anticancer effect on cervical cancer HeLa cells. The aim of this study was to investigate the anticancer activity of 12-deacetyl-12-epi-scalaradial against HeLa cells and to explore the mechanism. The results from a methylthiazolyldiphenyl-tetrazolium (MTT) assay suggested that 12-deacetyl-12-epi-scalaradial suppressed the proliferation of HeLa cells and flow cytometry analysis showed 12-deacetyl-12-epi-scalaradial could induce the apoptosis of HeLa cells in dose- and time-dependent manner. Western blotting analysis demonstrated that 12-deacetyl-12-epi-scalaradial triggered apoptosis via mediating the extrinsic pathway and was found to suppress MAPK/ERK pathway which was associate with cancer cell death. Nur77, a critical number of orphan nuclear receptors, plays diverse roles in tumor development as a transcription factor and has been considered as a promising anticancer drug target. The dual-luciferase reporter assays suggested that 12-deacetyl-12-epi-scalaradial could selectively enhance the trans-activation activity of Nur77. Furthermore, Western blotting analysis and fluorescence quenching showed that 12-deacetyl-12-epi-scalaradial could induce the phosphorylation of Nur77 and interact with the ligand-binding domain (LBD) of Nur77. Our research confirmed 12-deacetyl-12-epi-scalaradial as a potential agent for cervical cancer therapy and provided a view that 12-deacetyl-12-epi-scalaradial may be a modulator of Nur77.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/metabolismo , Poríferos/química , Sesterterpenos/farmacología , Neoplasias del Cuello Uterino/tratamiento farmacológico , Animales , Antineoplásicos/aislamiento & purificación , Proteínas Reguladoras de la Apoptosis/metabolismo , Proliferación Celular/efectos de los fármacos , Femenino , Células HeLa , Humanos , Fosforilación , Sesterterpenos/aislamiento & purificación , Transducción de Señal , Neoplasias del Cuello Uterino/enzimología , Neoplasias del Cuello Uterino/patología
5.
Chem Biodivers ; 17(9): e2000424, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32672903

RESUMEN

The chemical investigation on endophytic fungus Annulohypoxylon cf. stygium in leaves of Anoectochilus roxburghii (Wall.) Lindl. has been performed. Sixteen compounds were isolated and their structures were identified as (-)-notoamide A, (-)-notoamide B, (+)-versicolamide B, notoamide C, notoamide D, stephacidin A, sterigmatocystin, dihydrosterigmatocystin, secosterigmatocystin, versiconol, averufanin, kipukasin D, kipukasin E, diorcinal, palmarumycin CP2 and (-)-(3R)-mellein methyl ether, respectively, by spectroscopic analysis and comparison with literature data. All the compounds were isolated from Annulohypoxylon genus for the first time. Sterigmatocystin and palmarumycin CP2 showed selective cytotoxic activities against HepG2, HeLa, MCF-7 and HT-29.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Ascomicetos/química , Naftalenos/farmacología , Orchidaceae/microbiología , Hojas de la Planta/microbiología , Compuestos de Espiro/farmacología , Esterigmatocistina/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Ascomicetos/metabolismo , Línea Celular , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Naftalenos/química , Naftalenos/aislamiento & purificación , Compuestos de Espiro/química , Compuestos de Espiro/aislamiento & purificación , Esterigmatocistina/química , Esterigmatocistina/aislamiento & purificación
6.
Sensors (Basel) ; 20(21)2020 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-33114297

RESUMEN

As one of the core issues of autonomous vehicles, vehicle motion control directly affects vehicle safety and user experience. Therefore, it is expected to design a simple, reliable, and robust path following the controller that can handle complex situations. To deal with the longitudinal motion control problem, a speed tracking controller based on sliding mode control with nonlinear conditional integrator is proposed, and its stability is proved by the Lyapunov theory. Then, a linear parameter varying model predictive control (LPV-MPC) based lateral controller is formulated that the optimization problem is solved by CVXGEN. The nonlinear active disturbance rejection control (ADRC) method is applied to the second lateral controller that is easy to be implemented and robust to parametric uncertainties and disturbances, and the pure pursuit algorithm serves as a benchmark. Simulation results in different scenarios demonstrate the effectiveness of the proposed control schemes, and a comparison is made to highlight the advantages and drawbacks. It can be concluded that the LPV-MPC has some trouble to handle uncertainties while the nonlinear ADRC performs slight worse tracking but has strong robustness. With the parallel development of the control theory and computing power, robust MPC may be the future direction.

7.
Sensors (Basel) ; 20(8)2020 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-32316352

RESUMEN

How to make a controller robust and stable to reject the disturbance of uncertainty is an inevitable challenge. Aiming at addressing the lateral control problem for an autonomous road sweeper, a heading-error-based first order linear active disturbance rejective controller (HFO-LADRC) is proposed in this paper. To eliminate the lateral error and the heading error at the same time, a new model, called the heading-error-based model, is proposed for lateral motion, and the Lyapunov function was employed to explore the convergence ability of the heading error and lateral error. Since the heading-error-based model is first order, the ADRC is designed as first order and linear, and each module of the HFO-LADRC has been devised in detail. To ensure solution accuracy, the fourth order Runge-Kutta method was adopted as the differential system solver, and a typical ring scenario and a double lane-changing scenario were designed referencing the standard. Considering the obvious influence, wheelbase uncertainty, steering ratio uncertainty and Gaussian white noise disturbance were taken into account for the tests. The results illustrate that, in the case of both wheelbase uncertainty and steer ratio uncertainty, the HFO-LADRC has strong robustness and stability compared with a typical pure pursuit controller and classical SO-LADRC.

8.
J Oral Pathol Med ; 48(10): 911-918, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31323152

RESUMEN

BACKGROUND: Oral squamous cell carcinoma is the eighth most common cancer worldwide with a relatively high rate of metastasis (~40%). Previously, we showed that microRNA-138 serves as a functional tumor suppressor and plays an important role in oral squamous cell carcinoma metastasis. However, to date, microRNA-138 expression has not been examined in this tumor tissue. Herein, we demonstrated that microRNA-138 expression is downregulated in metastatic oral squamous cell carcinoma specimens using tissue microarray technology with in situ hybridization. METHODS: The study included 254 oral squamous cell carcinoma patients from two centers (160 from the Chengdu center and 90 from the Guangzhou center) and four healthy volunteers. RESULTS: Multivariate analysis showed that microRNA-138 expression was independent of tumor stage, age, gender, smoking, and alcohol consumption in oral squamous cell carcinoma patients. Interestingly, patients that expressed lower levels of microRNA-138 (determined by in situ hybridization) were more prone to regional lymph node metastasis and exhibited poorer outcomes. These findings support the role of microRNA-138 as a tumor suppressor in oral squamous cell carcinoma. CONCLUSION: In summary, the expression level of microRNA-138 is negatively correlated with oral squamous cell carcinoma metastasis; the lower the expression of microRNA-138, the higher the rate of metastasis and the poorer the prognosis of the patients. Therefore, our study confirms that microRNA-138 serves as a tumor suppressor and plays a functional role in oral squamous cell carcinoma tumor metastasis; microRNA-138 constitutes a promising prognosis biomarker and therapeutic target for oral squamous cell carcinoma with metastasis potential.


Asunto(s)
Carcinoma de Células Escamosas/genética , Genes Supresores de Tumor , MicroARNs/genética , Neoplasias de la Boca/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico
9.
J Asian Nat Prod Res ; 17(5): 519-31, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26043754

RESUMEN

Cochinchinones M-U (1-9), together with 12 known compounds (10-21), were isolated from the stems of Cratoxylum cochinchinense (Lour.) Blume. Their structures were determined on the basis of extensive spectroscopic data analyses. In addition, their retinoid X receptor-α transcriptional activities were evaluated using an in vitro assay.


Asunto(s)
Clusiaceae/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Medicamentos Herbarios Chinos/farmacología , Receptor alfa X Retinoide/efectos de los fármacos , Xantonas/aislamiento & purificación , Xantonas/farmacología , Medicamentos Herbarios Chinos/química , Humanos , Luciferasas de Luciérnaga/metabolismo , Estructura Molecular , Tallos de la Planta/química , Prenilación , Xantonas/química
10.
Zhongguo Zhong Yao Za Zhi ; 40(15): 2999-3004, 2015 Aug.
Artículo en Zh | MEDLINE | ID: mdl-26677700

RESUMEN

This article studied the chemical constituents from the aerial part of Vitis thunbergii var. taiwaniana. The 60% ethanol extract was eluted with 95% ethanol though HP-20 macroporous adsorption resin column. 12 compounds, including (1) betulinic acid, (2)2, 2, 2'-bis (4-hydroxyphenyl) propane bis (2, 3-epoxypropyl) ether, (3) eriodictyol, (4) trans-ε-viniferin, (5) (+)-cis-ε-viniferin, (6) kobophenol A, (7) ampelopsin A, (8) nepalensinol B, (9) cis-miyabenol C, (10) cis-vitisin B, (11) cis-gnetin H and (12) (+)-hopeaphenol, were separated by using normal phase silica gel, ODS, Sephdadex LH-20 column chromatographies and semi-preparative or preparative HPLC. Compounds 2, 5, 6, 8, 9, 10, 11 were separated from the genus Vitis for the first time and compounds 3, 7, 12 were separated from Vitis thunbergii var. taiwaniana for the first time. At a concentration of 50 µmol · L(-1), compound 6, 7 and 11 showed strong cytotoxicity against MCF-7 cell lines with the inhibition rate of 66.58%, 57.16%, 52.84%, respectively.


Asunto(s)
Vitis/química , Antineoplásicos Fitogénicos/farmacología , Humanos , Células MCF-7 , Extractos Vegetales/análisis , Extractos Vegetales/farmacología
11.
Carcinogenesis ; 35(12): 2660-9, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25187486

RESUMEN

Coumarins are plant-derived natural products with a broad range of known pharmacological activities including anticancer effects. However, the molecular mechanisms by which this class of promising compounds exerts their anticancer effects remain largely unknown. We report here that a furanocoumarin named apaensin could effectively induce apoptosis of cancer cells through its activation of Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK). Apoptosis induction by apaensin in cancer cells was suppressed by chemical inhibitors of JNK and p38 MAPK. Inhibition of the expression of orphan nuclear receptor Nur77 by small interfering RNA (siRNA) approach also abrogated the death effect of apaensin. Molecular analysis demonstrated that JNK activation was required for the nuclear export of Nur77, a known apoptotic event in cancer cells. Although p38 MAPK activation was not involved in Nur77 nuclear export, it was essential for Nur77 mitochondrial targeting through induction of Nur77 interaction with Bcl-2, which is also known to convert Bcl-2 from an antiapoptotic to a proapoptotic molecule. Together, our results identify a new natural product that targets orphan nuclear receptor Nur77 through its unique activation of JNK and p38 MAPK and provide insight into the complex regulation of the Nur77-Bcl-2 apoptotic pathway.


Asunto(s)
Apoptosis/efectos de los fármacos , Neoplasias de la Mama/patología , Furocumarinas/farmacología , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Neoplasias Pulmonares/patología , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Angelica/química , Western Blotting , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Proliferación Celular/efectos de los fármacos , Femenino , Humanos , Inmunoprecipitación , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Microscopía Fluorescente , Fosforilación , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Transducción de Señal/efectos de los fármacos , Células Tumorales Cultivadas
12.
Bioorg Med Chem Lett ; 24(11): 2504-7, 2014 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-24775302

RESUMEN

Two new bicyclic lactones, myrotheciumones A (1) and B (2) which possessed a rare ring-fusion system were isolated from Myrothecium roridum (M. roridum), an endophytic fungus of the medicinal herb plant Ajuga decumbens (A. decumbens) via an in vitro cytotoxicity assay. Structures were deduced from 1D and 2D NMR (Nuclear magnetic resonance) data. Myrotheciumone A's in vitro cytotoxicity and apoptotic activity were evaluated and myrotheciumone A was shown to exert cytotoxicity via inducing apoptosis in cancer cell line.


Asunto(s)
Ajuga/microbiología , Antineoplásicos/farmacología , Ascomicetos/química , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Lactonas/farmacología , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Apoptosis/efectos de los fármacos , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Compuestos Bicíclicos Heterocíclicos con Puentes/aislamiento & purificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Células Hep G2 , Humanos , Lactonas/química , Lactonas/aislamiento & purificación , Estructura Molecular , Relación Estructura-Actividad
13.
J Ethnopharmacol ; 326: 117987, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38423407

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Paeoniae Radix Rubra (PRR) is the dried root of Paeonia lactiflora Pall, which has been widely used to anti-thrombotic, lipid-lowering, anti-spasmodic, antioxidant, antibacterial, hepatoprotective, and anti-tumor in Chinese clinical practice. Recent research has demonstrated that PRR plays a significant anti-tumor role in animal models of tumor-bearing. AIM OF THE STUDY: There has not been the evaluation of the anti-tumor effects of PRR. This study conducts a meta-analysis to assess the anti-tumor efficacy of PRR on animal models, providing scientific evidence for clinical application of PRR in the adjuvant therapy of tumors. MATERIALS AND METHODS: English databases (PubMed, The Cochrane Library, Embase, and Web of Science) and Chinese databases (CNKI, WanFang, SinoMed, CTSJ-VIP) were used to search all pertinent animal studies investigating the anti-tumor effects of PRR and its extracts. The quality of the included studies was evaluated using the SYRCLE animal experiment risk assessment tool, and statistical analysis was carried out using Revman 5.3 software. Egger's test and funnel plots were used to assess potential publication bias in the studies. RESULTS: The initial search produced a total of 3905 potentially pertinent studies, and 24 studies met the inclusion criteria. These studies included animal tumor models of hepatocellular carcinoma, lung cancer, sarcoma, bladder cancer, leukemia, colon cancer, glioblastoma, and pancreatic cancer. The meta-analysis findings demonstrated that both PRR and its extracts significantly inhibited tumor growth in animals. Compared with the control group, PRR substantively inhibited tumor volume (SMD, -3.09; 95% CI, [-4.05, -2.13]; P < 0.0001), reduced tumor weight (SMD, -1.08; 95% CI, [-1.37, -0.78]; P < 0.0001), decreased tumor number (SMD, -2.16; 95% CI, [-3.45, -0.86]; P = 0.001), and prolonged the survival duration time (SMD, 0.97; 95% CI, [0.23, 1.71]; P = 0.01) on the experimental animals. CONCLUSIONS: PRR displayed a potential therapeutic efficacy on eight tumors in animal models including hepatocellular carcinoma, lung cancer, sarcoma, bladder cancer, leukemia, colon cancer, glioblastoma, and pancreatic cancer. However, the quality and quantity of included studies may affect the accuracy of positive results. In the future, more high-quality randomized controlled animal experiments are need for meta-analysis.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias del Colon , Medicamentos Herbarios Chinos , Glioblastoma , Leucemia , Neoplasias Hepáticas , Neoplasias Pulmonares , Paeonia , Neoplasias Pancreáticas , Extractos Vegetales , Sarcoma , Neoplasias de la Vejiga Urinaria , Animales , Modelos Animales , Neoplasias Hepáticas/tratamiento farmacológico
14.
Zhongguo Zhong Yao Za Zhi ; 38(11): 1751-6, 2013 Jun.
Artículo en Zh | MEDLINE | ID: mdl-24010290

RESUMEN

OBJECTIVE: To study the chemical constituents of Elephantopus tomentosus. METHOD: The compounds were isolated by repeated HP20 macro porous adsorption resin column combined with Sephadex LH-20, ODS and silica gel chromatographies. The structures were identified on the basis of extensive spectroscopic data analysis and by comparison of their spectral data reported. RESULT: Eighteen compounds were identified as 2-deethoxy-2beta-hydroxyphantomolin (1), 2beta-hydroxy-2-deethoxy-8-O-deacylphantomolin-8-O-tiglinate (2), 2beta-methoxy-2-deethoxyphantomolin (3), 2beta-methoxy-2-deethoxy-8-O-deacylphantomolin-8-O-tiglinate (4), molephantin (5), molephantinin (6), tricin (7), luteolin (8), quercetin (9), 3beta-friedelinol (10), 3beta-hydroxyolean-12-en-28-oic acid (11), 3, 5-di-O-caffeoyl quinic acid (12), 3,4-di-O-caffeoyl quinic acid (13), syringaresinol-4-beta-D-glucopyranoside (14), xylogranatinin (15), byzantionoside B (16), 2'-hydroxycinnamaldehyde (17), and caffeic acid ethyl ester (18). CONCLUSION: Compounds 9, 11, 14-18 were separated from Elephantopus for the first time.


Asunto(s)
Asteraceae/química , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Espectrometría de Masas , Estructura Molecular
15.
Front Pharmacol ; 14: 1124240, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36874033

RESUMEN

Celastrol, a triterpene derived from Thunder God Vine (Tripterygium wilfordii Hook f; Celastraceae), a traditional Chinese herb, has promising anticancer activity. The present study aimed to elucidate an indirect mechanism of celastrol-mediated alleviation of hepatocellular carcinoma (HCC) via gut microbiota-regulated bile acid metabolism and downstream signaling. Here, we constructed a rat model of orthotopic HCC and performed 16S rDNA sequencing and UPLC-MS analysis. The results showed that celastrol could regulate gut bacteria; suppress the abundance of Bacteroides fragilis; raise the levels of glycoursodeoxycholic acid (GUDCA), a bile acid; and alleviate HCC. We found that GUDCA suppressed cellular proliferation and induced the arrest of mTOR/S6K1 pathway-associated cell cycle G0/G1 phase in HepG2 cells. Further analyses using molecular simulations, Co-IP, and immunofluorescence assays revealed that GUDCA binds to farnesoid X receptor (FXR) and regulates the interaction of FXR with retinoid X receptor a (RXRα). Transfection experiments using the FXR mutant confirmed that FXR is essential for GUCDA-mediated suppression of HCC cellular proliferation. Finally, animal experiments showed that the treatment with the combination of celastrol/GUDCA alleviated the adverse effects of celastrol alone treatment on body weight loss and improved survival in rats with HCC. In conclusion, the findings of this study suggest that celastrol exerts an alleviating effect on HCC, in part via regulation of the B. fragilis-GUDCA-FXR/RXRα-mTOR axis.

16.
Vaccines (Basel) ; 11(2)2023 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-36851173

RESUMEN

Coronavirus disease 2019 (COVID-19), beginning in December 2019, has spread worldwide, leading to the death of millions. Owing to the absence of definitive treatment, vaccination against COVID-19 emerged as an effective strategy against the spread of the pandemic. Acceptance of the COVID-19 vaccine has advanced considerably, and vaccine-related research has significantly increased over the past three years. This study aimed to evaluate the content and external characteristics of COVID-19 vaccine-related literature for tracking research trends related to the global COVID-19 vaccine with the means of bibliometrics and visualization maps. A total of 18,285 records in 3499 journals were retrieved in the Web of Science Core Collection database and included in the final analysis. China was the first to focus on COVID-19 vaccine research, while European and American countries started late but developed rapidly. The USA and the UK are the top contributors to COVID-19 vaccine development, with the largest number of publications. The University of Washington and Harvard Medical School were the leading institutions, while Krammer, F. from Icahn School of Medicine at Mount Sinai was the author most active and influential to the topic. The New England Journal of Medicine had the highest number of citations and the highest TLS, and was the most cited and influential journal in the field of COVID-19 vaccine research. COVID-19 vaccine research topics and hotspots focused on populations' attitudes towards vaccination, immunity-related information analysis of spike proteins, the effectiveness and side effects of the COVID-19 vaccine, and the public management of epidemic transmission. The findings of this study provide the global status, research hotspots and potential trends in the field of COVID-19 vaccine research, which will assist researchers in mastering the knowledge structure, and evaluating and guiding future developmental directions of COVID-19 vaccine.

17.
Micromachines (Basel) ; 14(6)2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37374766

RESUMEN

A hard issue in the field of microrobots is path planning in complicated situations with dense obstacle distribution. Although the Dynamic Window Approach (DWA) is a good obstacle avoidance planning algorithm, it struggles to adapt to complex situations and has a low success rate when planning in densely populated obstacle locations. This paper suggests a multi-module enhanced DWA (MEDWA) obstacle avoidance planning algorithm to address the aforementioned issues. An obstacle-dense area judgment approach is initially presented by combining Mahalanobis distance, Frobenius norm, and covariance matrix on the basis of a multi-obstacle coverage model. Second, MEDWA is a hybrid of enhanced DWA (EDWA) algorithms in non-dense areas with a class of two-dimensional analytic vector field methods developed in dense areas. The vector field methods are used instead of the DWA algorithms with poor planning performance in dense areas, which greatly improves the passing ability of microrobots over dense obstacles. The core of EDWA is to extend the new navigation function by modifying the original evaluation function and dynamically adjusting the weights of the trajectory evaluation function in different modules using the improved immune algorithm (IIA), thus improving the adaptability of the algorithm to different scenarios and achieving trajectory optimization. Finally, two scenarios with different obstacle-dense area locations were constructed to test the proposed method 1000 times, and the performance of the algorithm was verified in terms of step number, trajectory length, heading angle deviation, and path deviation. The findings indicate that the method has a smaller planning deviation and that the length of the trajectory and the number of steps can both be reduced by about 15%. This improves the ability of the microrobot to pass through obstacle-dense areas while successfully preventing the phenomenon of microrobots going around or even colliding with obstacles outside of dense areas.

18.
J Biol Chem ; 286(16): 13937-44, 2011 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-21378168

RESUMEN

Tumor suppressor menin, the product of the MEN1 gene, plays a key role in controlling histone 3 lysine 4 trimethylation (H3K4me3) and gene transcription, which can regulate proliferation, apoptosis, and differentiation. However, little is known as to whether menin controls gene expression and cell proliferation and survival via regulating Polycomb group (PcG) protein complex/H3K27me3. Here we show that menin specifically represses transcription factor Paired box gene 2 (Pax2) through PcG-mediated H3K27me3 and Wilms tumor suppressor protein (WT1), a zinc finger domain-containing DNA-binding protein. Menin does not directly bind to the Pax2 locus, instead, it up-regulates WT1 expression. WT1 recruits PcG complex to the Pax2 promoter and represses expression of Pax2 through PcG-dependent H3K27me3. Moreover, WT1 also interacts with DNA methyltransferase 1 (DNMT1), and recruits DNMT1 to the Pax2 promoter, resulting in hypermethylation of CpG in the Pax2 promoter. Together, these studies have uncovered a novel epigenetic mechanism whereby menin regulates H3K27me3 and promoter DNA methylation via WT1 and suggest that WT1 protein plays an important, yet previously unappreciated role in regulating the function of the menin/PcG axis, H3K27 methylation, and DNA methylation, resulting in repression of gene transcription.


Asunto(s)
Histona Demetilasas con Dominio de Jumonji/metabolismo , Animales , Apoptosis , Línea Celular , Proliferación Celular , Islas de CpG , ADN/metabolismo , Ratones , Ratones Transgénicos , Factor de Transcripción PAX2/metabolismo , Unión Proteica , Proteínas Proto-Oncogénicas/metabolismo , Transfección , Proteínas WT1/metabolismo
19.
Front Med (Lausanne) ; 9: 975229, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36186766

RESUMEN

The BOPPPS teaching strategy has been used recently in many medical courses as an improved and more practical pedagogy in China. Nevertheless, the effectiveness of this pedagogy has not been fully assessed in terms of knowledge and skill outcomes in medical education. This meta-analysis aimed to evaluate the effectiveness of the BOPPPS strategy compared with traditional lecture-based learning (LBL) in Chinese medical education. The English electronic databases of Web of Science, PubMed, Embase, and the Cochrane Library and the Chinese electronic databases of CNKI, CQVIP, Wanfang, and CBM were used to search the publications related to the BOPPPS teaching strategy before 6 Jun 2022. Eligibility publications were retrieved and the data were extracted by two researchers independently according to the predefined inclusion and exclusion criteria. Quality analysis was performed using the Cochrane risk-of-bias tool, and the meta-analysis was performed using RevMan 5.3 and StataSE. We retrieved 367 records and 41 studies with a total of 5,042 medical students in the meta-analysis, which included 34 randomized controlled trials (RCTs) and 7 Cohort studies. In the cumulative meta-analysis, BOPPPS strategy significantly increased skill scores (SS) (SMD: 1.15, 95% CI: 1.00-1.30, P < 0.00001), knowledge examination scores (KES) (SMD: 1.56, 95% CI: 1.24-1.89, P < 0.00001), comprehensive ability scores (CAS) (SMD: 1.22, 95%CI: 0.85-1.59; P < 0.00001), and teaching satisfaction (TS) (OR: 3.64; 95%CI: 2.97-4.46; P < 0.0001) compared to the LBL model among those medical students. Statistically similar results were obtained in the sensitivity analysis. These results showed that the BOPPPS method is an effective teaching strategy for Chinese medical students to improve SS, knowledge scores, CAS, and TS when compared with LBL in medical education. Because of the limited quantity and quality of the included studies, further rigorous studies are needed to conclude with more confidence.

20.
Nat Prod Res ; 36(15): 3840-3849, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33648391

RESUMEN

One undescribed lignan, one new natural product, along with fourteen known compounds, were isolated from the roots of Ficus hirta. The structures of the isolates were elucidated by comprehensive spectroscopic technologies, including UV, IR, HRESIMS, and NMR. The absolute configuration of 1 was determined by comparison of experimental and calculated ECD data. The cytotoxicity of all the compounds against HeLa and HepG2 cell lines was evaluated and compound 7 showed considerable cytotoxic effect towards HepG2 cells. Also, the apoptotic effect of 7 on HepG2 cells and the effect of 7 on the key proteins (p-JNK and p-p38) in MAPK (Mitogen-activated protein kinases) pathways were studied by flow cytometry and western blotting experiment. As a result, compound 7 induced the apoptosis of HepG2 cells, and dose-dependently increased the phosphorylation of JNK and p38. Thus, 7 might trigger HepG2 cells apoptosis via JNK/p38 MAPK signaling pathway.


Asunto(s)
Antineoplásicos , Ficus , Lignanos , Antineoplásicos/farmacología , Apoptosis , Ficus/química , Células Hep G2 , Humanos , Lignanos/análisis , Lignanos/farmacología , Raíces de Plantas/química , Proteínas Quinasas p38 Activadas por Mitógenos/análisis , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/farmacología
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