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1.
J Med Chem ; 66(4): 2566-2588, 2023 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-36749735

RESUMEN

The development of orally bioavailable, furanopyrimidine-based double-mutant (L858R/T790M) EGFR inhibitors is described. First, selectivity for mutant EGFR was accomplished by replacing the (S)-2-phenylglycinol moiety of 12 with either an ethanol or an alkyl substituent. Then, the cellular potency and physicochemical properties were optimized through insights from molecular modeling studies by implanting various solubilizing groups in phenyl rings A and B. Optimized lead 52 shows 8-fold selective inhibition of H1975 (EGFRL858R/T790M overexpressing) cancer cells over A431 (EGFRWT overexpressing) cancer cells; western blot analysis further confirmed EGFR mutant-selective target modulation inside the cancer cells by 52. Notably, 52 displayed in vivo antitumor effects in two different mouse xenograft models (BaF3 transfected with mutant EGFR and H1975 tumors) with TGI = 74.9 and 97.5% after oral administration (F = 27%), respectively. With an extraordinary kinome selectivity (S(10) score of 0.017), 52 undergoes detailed preclinical development.


Asunto(s)
Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Receptores ErbB , Neoplasias Pulmonares , Inhibidores de Proteínas Quinasas , Pirimidinas , Animales , Humanos , Ratones , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Línea Celular Tumoral , Proliferación Celular , Resistencia a Antineoplásicos , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/genética , Neoplasias Pulmonares/tratamiento farmacológico , Mutación , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/farmacología , Administración Oral , Pirimidinas/administración & dosificación , Pirimidinas/farmacología
2.
Artículo en Inglés | MEDLINE | ID: mdl-36417735

RESUMEN

In this article, a modified mutual information maximization (InfoMax) framework, named channel capacity maximization (CapMax), is proposed and applied to learn informative representations for dynamic networks with time-varying topology and/or time-evolving node attributes. The CapMax is based on the network information theory for multiuser communication, where the representation model is treated as a multiaccess communication channel with memory and feedback. Without requirements of the backbone structure, the learning objective of our CapMax is maximizing the channel capacity, which is measured by directed information (DI) rather than mutual information. For efficient implementation, we design an estimator of the channel capacity through the combination of graph neural networks (GNNs) and recurrent neural networks (RNNs). Under some mild conditions, we theoretically prove that DI is a better measure than mutual information in capturing useful information. The experiments are conducted on multiple real-world dynamic network datasets, and the outperformance of our CapMax on different backbone models on link detection and prediction validates the effectiveness of modeling the representation model as a communication channel.

3.
Opt Express ; 30(6): 8709-8722, 2022 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-35299317

RESUMEN

Skin-elasticity measurements can assist in the clinical diagnosis of skin diseases, which has important clinical significance. Accurately determining the depth-resolved elasticity of superficial biological tissue is an important research direction. This paper presents an optical coherence elastography technique that combines surface acoustic waves and shear waves to obtain the elasticity of multilayer tissue. First, the phase velocity of the high-frequency surface acoustic wave is calculated at the surface of the sample to obtain the Young's modulus of the top layer. Then, the shear wave velocities in the other layers are calculated to obtain their respective Young's moduli. In the bilayer phantom experiment, the maximum error in the elastic estimation of each layer was 2.2%. The results show that the proposed method can accurately evaluate the depth-resolved elasticity of layered tissue-mimicking phantoms, which can potentially expand the clinical applications of elastic wave elastography.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Módulo de Elasticidad , Elasticidad , Diagnóstico por Imagen de Elasticidad/métodos , Fantasmas de Imagen , Tomografía de Coherencia Óptica/métodos
4.
J Med Chem ; 64(19): 14477-14497, 2021 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-34606263

RESUMEN

Colony-stimulating factor-1 receptor (CSF1R) is implicated in tumor-associated macrophage (TAM) repolarization and has emerged as a promising target for cancer immunotherapy. Herein, we describe the discovery of orally active and selective CSF1R inhibitors by property-driven optimization of BPR1K871 (9), our clinical multitargeting kinase inhibitor. Molecular docking revealed an additional nonclassical hydrogen-bonding (NCHB) interaction between the unique 7-aminoquinazoline scaffold and the CSF1R hinge region, contributing to CSF1R potency enhancement. Structural studies of CSF1R and Aurora kinase B (AURB) demonstrated the differences in their back pockets, which inspired the use of a chain extension strategy to diminish the AURA/B activities. A lead compound BPR1R024 (12) exhibited potent CSF1R activity (IC50 = 0.53 nM) and specifically inhibited protumor M2-like macrophage survival with a minimal effect on antitumor M1-like macrophage growth. In vivo, oral administration of 12 mesylate delayed the MC38 murine colon tumor growth and reversed the immunosuppressive tumor microenvironment with the increased M1/M2 ratio.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias del Colon/tratamiento farmacológico , Descubrimiento de Drogas , Agentes Inmunomoduladores/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Receptor de Factor Estimulante de Colonias de Macrófagos/antagonistas & inhibidores , Administración Oral , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Línea Celular Tumoral , Neoplasias del Colon/patología , Agentes Inmunomoduladores/administración & dosificación , Agentes Inmunomoduladores/química , Masculino , Ratones , Ratones Endogámicos C57BL , Neoplasias Experimentales , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/química , Ratas Sprague-Dawley , Relación Estructura-Actividad
5.
Bioorg Chem ; 98: 103689, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32171993

RESUMEN

In an effort to develop new cancer therapeutics, we have reported clinical candidate BPR1K871 (1) as a potentanticancercompound in MOLM-13 and MV4-11 leukemia models, as well as in colorectal and pancreatic animal models. As BPR1K871 lacks oral bioavailability, we continued searching for orally bioavailable analogs through drug-like property optimization. We optimized both the physicochemical properties (PCP) as well as in vitro rat liver microsomal stability of 1, with concomitant monitoring of aurora kinase enzyme inhibition as well as cellular anti-proliferative activity in HCT-116 cell line. Structural modification at the 6- and 7-position of quinazoline core of 1 led to the identification of 34 as an orally bioavailable (F% = 54) multi-kinase inhibitor, which exhibits potent anti-proliferative activity against various cancer cell lines. Quinazoline 34 is selected as a promising oral lead candidate for further preclinical evaluation.


Asunto(s)
Antineoplásicos/farmacología , Aurora Quinasas/antagonistas & inhibidores , Descubrimiento de Drogas , Inhibidores de Proteínas Quinasas/farmacología , Quinazolinas/farmacología , Administración Oral , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Aurora Quinasas/metabolismo , Disponibilidad Biológica , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Células HCT116 , Humanos , Masculino , Estructura Molecular , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/química , Quinazolinas/administración & dosificación , Quinazolinas/química , Ratas , Ratas Sprague-Dawley , Relación Estructura-Actividad
6.
Nat Commun ; 10(1): 4554, 2019 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-31591404

RESUMEN

Explaining colour variation among animals at broad geographic scales remains challenging. Here we demonstrate how deep learning-a form of artificial intelligence-can reveal subtle but robust patterns of colour feature variation along an ecological gradient, as well as help identify the underlying mechanisms generating this biogeographic pattern. Using over 20,000 images with precise GPS locality information belonging to nearly 2,000 moth species from Taiwan, our deep learning model generates a 2048-dimension feature vector that accurately predicts each species' mean elevation based on colour and shape features. Using this multidimensional feature vector, we find that within-assemblage image feature variation is smaller in high elevation assemblages. Structural equation modeling suggests that this reduced image feature diversity is likely the result of colder environments selecting for darker colouration, which limits the colour diversity of assemblages at high elevations. Ultimately, with the help of deep learning, we will be able to explore the endless forms of natural morphological variation at unpreceded depths.


Asunto(s)
Inteligencia Artificial , Biodiversidad , Color , Variación Genética , Insectos/genética , Pigmentación de la Piel/genética , Altitud , Animales , Clima , Aprendizaje Profundo , Insectos/fisiología , Mariposas Nocturnas/clasificación , Mariposas Nocturnas/genética , Mariposas Nocturnas/fisiología , Filogenia , Especificidad de la Especie , Temperatura
7.
Transfusion ; 54(12): 3222-31, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25041587

RESUMEN

BACKGROUND: The molecular mechanism for the formation of the P1/P2 blood groups remains unsolved. It has been shown that the P1/P2 polymorphism is connected to the different A4GALT gene expression levels in P1 and P2 red blood cells. STUDY DESIGN AND METHODS: The present investigation conducted a pilot investigation that involved the detailed and stepwise screening of single-nucleotide polymorphisms (SNPs) in the A4GALT gene, followed by a larger-scale association study. The transcription-inducing activity by the different genotypes of SNPs was analyzed using reporter assays. RESULTS: A total of 416 different SNP sites in the A4GALT genes from four P1 and four P2 individuals were analyzed in the pilot investigation, and 11 SNP sites, distributed in the A4GALT Intron 1 region, exhibited an association with the P1/P2 phenotypes. In the follow-up association study, the genotypes at the 11 SNPs of a total of 338 individuals across four different ethnic populations were determined, and the results show that two SNPs, rs2143918 and rs5751348, are consistently associated with the P1/P2 phenotypes. Reporter assays demonstrated significantly higher transcription-inducing activity by the SNPs bearing the P(1)-allele genotype than by the SNPs bearing the P(2)-allele genotype and that the difference in transcriptional activity was determined by the different genotypes at SNP rs5751348. CONCLUSION: The results of this investigation demonstrate a consistent association of A4GALT SNPs rs2143918 and rs5751348 with the P1/P2 phenotypes and suggest that SNP rs5751348 may lead to allelic variations in A4GALT gene expression and consequently leads to the formation of the P1/P2 phenotypes.


Asunto(s)
Alelos , Galactosiltransferasas/genética , Regulación de la Expresión Génica/genética , Genotipo , Sistema del Grupo Sanguíneo P/genética , Polimorfismo de Nucleótido Simple , Femenino , Galactosiltransferasas/biosíntesis , Humanos , Intrones/genética , Masculino , Sistema del Grupo Sanguíneo P/metabolismo , Proyectos Piloto
8.
PLoS One ; 9(3): e92849, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24667663

RESUMEN

Graves disease (GD) is an autoimmune disease. Macrophage migration inhibitory factor (MIF) is a potent cytokine that plays an important role in the regulation of immune responses. Two polymorphisms in the promoter region of MIF, rs5844572 and rs755622, are known to affect MIF expression. The purpose of this study was to investigate the relationship between polymorphisms in the MIF gene promoter and the severity of GD. A total of 677 individuals, including 481 GD patients and 196 ethnically matched healthy controls, were genotyped to identify differences in the distribution of the MIF polymorphisms rs5844572 and rs755622. Although there were no significant differences in the allele or genotype distributions among patients with different grades of goiter in GD and healthy controls, the distribution of the C allele, especially C/C genotype, of the rs755622 single nucleotide polymorphism (SNP) in MIF, may be as a risk factor for goiter initiation whereas a protector against development of severe goiter in patients with untreated GD (p<0.05). A goiter-developmental model incorporating genetic (MIF SNP rs755622) and environmental risk factors (gender, radioiodine treatment, thyroid gland surgery and vitiligo) significantly increased the prediction accuracy. Further studies are required to address the role of MIF polymorphisms, as well as their association with other candidate genes, in GD.


Asunto(s)
Enfermedad de Graves/genética , Oxidorreductasas Intramoleculares/genética , Factores Inhibidores de la Migración de Macrófagos/genética , Polimorfismo de Nucleótido Simple , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Pueblo Asiatico , Femenino , Regulación de la Expresión Génica , Enfermedad de Graves/metabolismo , Enfermedad de Graves/terapia , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Taiwán
9.
Glycobiology ; 24(4): 359-67, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24418929

RESUMEN

The cell surface sialyl Lewis a (sLe(a)) and sialyl Lewis x (sLe(x)) antigens, which are built on the terminals of glyco-structures called poly-N-acetyllactosamine (LacNAc) chains, have been shown to play a critical role in the metastasis of colon cancer. In the present investigation, expression of the B3GNT7 gene, which encodes a ß-1,3-N-acetylglucosaminyltransferase that mainly acts on and extends sulfated poly-LacNAc chains, was found to be markedly suppressed during the oncogenetic processes associated with colon cancer. DNA methylation in the promoter region of the B3GNT7 gene was found to play a significant role in the suppression of the B3GNT7 gene in colon cancer cells. The results obtained from Transwell experiments and the nude mice xenograft model demonstrated that ectopic expression of the B3GNT7 gene in colon cancer cells diminished the migration capability and the liver-metastasis potential, respectively, of colon cancer cells. Flow cytometric analysis showed that expression of cell surface sLe(a) and sLe(x) antigens was decreased in colon cancer cells when the B3GNT7 gene was ectopically expressed. Taken together, the results of the present investigation suggest a link between suppression of B3GNT7 gene expression and elevation of sLe(a)/sLe(x) antigen expressions on the surface of cells and that this consequently promotes the metastasis potential of cancer cells as part of the colon cancer oncogenetic process.


Asunto(s)
Neoplasias del Colon/genética , Neoplasias del Colon/patología , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas/secundario , N-Acetilglucosaminiltransferasas/genética , Metástasis de la Neoplasia/genética , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Animales , Línea Celular Tumoral , Movimiento Celular/genética , Neoplasias del Colon/metabolismo , Perfilación de la Expresión Génica , Células HCT116 , Células HT29 , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Ratones , Ratones Desnudos , N-Acetilglucosaminiltransferasas/biosíntesis , N-Acetilglucosaminiltransferasas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo
10.
J Biomed Nanotechnol ; 9(9): 1617-23, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23980509

RESUMEN

The purpose of this research was to investigate the possibility of dexamethasone (DEX)-loaded PLGA-TPGS nanoparticles (NPs) in rabbits after intravitreal administration for the treatment of posterior segment diseases. The DEX-loaded PLGA-TPGS NPs were fabricated and characterized in terms of surface morphology, particle size and size distribution, entrapment efficiency, and in vitro drug release. The animals were classified randomly into two groups: experimental group with thirty rabbits, and control group with eighteen rabbits. Rabbits in the experimental group received intravitreal injections of 0.1 mL of DEX-loaded PLGA-TPGS NPs suspension and the control rabbits received intravitreal injection of 0.1 mL DEX (20 g/L in saline). The DEX concentrations in plasma and the ocular tissues such as the cornea, aqueous humor, lens, iris, vitreous humor, and chorioretina were determined by HPLC. The DEX-loaded PLGA-TPGS nanoparticle suspension were transparent and maintained a sustained release of DEX for about 45 days in vitreous and provided relatively constant DEX levels for more than 30 days with a mean concentration of 3.93 mg/L. Based on the area-under-the-curve (AUC), the bioavailability of DEX in the experimental group was significantly higher than that in the control group administrated with regular DEX. These results suggest that intravitreal administration of DEX-loaded PL.3A-TPGS NPs leads to a sustained release of DEX with a high bioavailability, providing a basis for a novel approach to treat posterior segment diseases.


Asunto(s)
Dexametasona/administración & dosificación , Dexametasona/farmacocinética , Ácido Láctico/química , Nanocápsulas/administración & dosificación , Nanocápsulas/química , Ácido Poliglicólico/química , Segmento Posterior del Ojo/metabolismo , Vitamina E/análogos & derivados , Animales , Antiinflamatorios/administración & dosificación , Antiinflamatorios/química , Antiinflamatorios/farmacocinética , Dexametasona/química , Difusión , Oftalmopatías/tratamiento farmacológico , Oftalmopatías/metabolismo , Inyecciones Intravítreas/métodos , Ensayo de Materiales , Tasa de Depuración Metabólica , Polietilenglicoles/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Conejos , Distribución Tisular , Vitamina E/química
11.
J Thromb Thrombolysis ; 34(4): 533-40, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22802079

RESUMEN

To investigate the stenotic coexistence among coronary, renal and extracranial arteries and check the predictive value of stenosis between these arteries in Chinese patients. The stenosis of three arteries was evaluated by angiography in 1,228 Chinese patients with clinically diagnosed coronary artery disease (CAD) or high CAD risk factors. Based on the criteria of stenotic diameter of ≥50%, we found that the rate of stenosis for the coronary artery was highest (48.5%), extracranial artery stenosis rate was intermediate at 20.2% and the renal artery with the stenosis rate of 14.3% was the lowest. The stenotic coexistence rates were 14.3% between the coronary and extracranial arteries, 10.9 % between coronary and renal arteries, 10.1% between the extracranial and renal arteries, and only 2.69% among all three arteries. The stenosis predictive value of the coronary artery for extracranial or renal arteries was lower, but the non-stenosis predictive value was higher. The predictive value of extracranial or renal artery for coronary artery stenosis was higher, while the non-stenosis predictive value was lower. Both the stenosis and non-stenosis predictive values were higher between the extracranial and renal arteries. Cohen's Kappa value was less than 0.40 between coronary and extracrainal or renal artery but more than 0.40 between extracranial and renal artery. The results were similar when the criteria of stenosis were judged as ≥75 or ≥25% respectively. We also did analysis within the subgroups with hypertension, diabetes, stroke and transient ischemia attach, got similar results. For Chinese patients with clinically diagnosed CAD or with highly risk factors, non-stenosis of the coronary artery is indicative of reduced stenosis of the extracranial and renal arteries, while extracranial or renal arteries stenosis is indicative of increased coronary artery stenosis.


Asunto(s)
Estenosis Carotídea , Estenosis Coronaria , Obstrucción de la Arteria Renal , Adulto , Factores de Edad , Anciano de 80 o más Años , Pueblo Asiatico , Estenosis Carotídea/complicaciones , Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/epidemiología , Angiografía Cerebral , China/epidemiología , Angiografía Coronaria , Estenosis Coronaria/complicaciones , Estenosis Coronaria/diagnóstico por imagen , Estenosis Coronaria/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obstrucción de la Arteria Renal/complicaciones , Obstrucción de la Arteria Renal/diagnóstico por imagen , Obstrucción de la Arteria Renal/epidemiología , Factores de Riesgo
12.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 25(5): 1146-9, 2008 Oct.
Artículo en Chino | MEDLINE | ID: mdl-19024464

RESUMEN

Poly-hemoglobin is the active component of hemoglobin-based blood substitutes. The excess reactivity of glutaraldehyde with hemoglobin in solution leads to poly-hemoglobin of a wide molecular weight distribution and a high average molecular weight. A new polymerization method has been tested to decrease the molecular weight distribution and the average molecular weight. The poly-hemoglobin with lower degree of modification (polymerization) was found enriched on the cation exchange columns and further polymerized with glutaraldehyde. The poly-hemoglobin of narrower molecular weight distribution has been prepared in this way.


Asunto(s)
Sustitutos Sanguíneos/síntesis química , Hemoglobinas/química , Fosfato de Piridoxal/análogos & derivados , Sustitutos Sanguíneos/química , Cromatografía por Intercambio Iónico/métodos , Hemoglobinas/síntesis química , Humanos , Fosfato de Piridoxal/síntesis química , Fosfato de Piridoxal/química
13.
Artículo en Chino | MEDLINE | ID: mdl-17639705

RESUMEN

OBJECTIVE: To analyze the status of Leishmania infantum asymptomatic infection in human population of a Kala-azar endemic area in Wenxian County, Gansu Province, and to evaluate the tests used. METHODS: Blood samples were tested by PCR using two pairs of primers, RV1-RV2 and K13A-K13B, for detecting Leishmania-specific DNA. ELISA and rK39-dipstick were used to detect Leishmania-specific antibodies. RESULTS: The positive rate of PCR, ELISA and rK39-dipstick was 30.9%(83/269). 24.2%(65/269) and 0 (0/269) respectively. CONCLUSION: The prevalence of asymptomatic infection of L. infantum in humans is high in the area. PCR test based on RV1-RV2 and K13A-K13B primer pairs is a sensitive and specific method for detecting the asymptomatic infection.


Asunto(s)
Leishmaniasis/epidemiología , Leishmaniasis/parasitología , Animales , Anticuerpos Antiprotozoarios/sangre , China/epidemiología , ADN Protozoario/genética , Ensayo de Inmunoadsorción Enzimática , Humanos , Lactante , Leishmania infantum/genética , Leishmania infantum/inmunología , Leishmaniasis/sangre , Reacción en Cadena de la Polimerasa
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