Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Sci Rep ; 13(1): 2124, 2023 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-36746997

RESUMEN

Dicentric chromosome analysis is the gold standard for biological dose assessment. To enhance the efficiency of biological dose assessment in large-scale radiation catastrophes, automatic identification of dicentric chromosome images is a promising and objective method. In this paper, an automatic identification method for dicentric chromosome images using two-stage convolutional neural network is proposed based on Giemsa-stained automatic microscopic imaging. To automatically segment the adhesive chromosome masses, a k-means based adaptive image segmentation and watershed segmentation algorithm is applied. The first-stage CNN is used to identify the dicentric chromosome images from all the images and the second-stage CNN works to specifically identify the dicentric chromosome images. This two-stage CNN identification method can effectively detects chromosome images with concealed centromeres, poorly expanded and long-armed entangled chromosomes, and tricentric chromosomes. The novel two-stage CNN method has a chromosome identification accuracy of 99.4%, a sensitivity of 85.8% sensitivity, and a specificity of 99.6%, effectively reducing the false positive rate of dicentric chromosome. The analysis speed of this automatic identification method can be 20 times quicker than manual detection, providing a valuable reference for other image identification situations with small target rates.


Asunto(s)
Trastornos de los Cromosomas , Humanos , Redes Neurales de la Computación , Algoritmos , Centrómero , Procesamiento de Imagen Asistido por Computador/métodos
2.
Sci Rep ; 12(1): 3913, 2022 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-35273270

RESUMEN

Cytokinesis block micronucleus (CBMN) assay is a widely used radiation biological dose estimation method. However, the subjectivity and the time-consuming nature of manual detection limits CBMN for rapid standard assay. The CBMN analysis is combined with a convolutional neural network to create a software for rapid standard automated detection of micronuclei in Giemsa stained binucleated lymphocytes images in this study. Cell acquisition, adhesive cell mass segmentation, cell type identification, and micronucleus counting are the four steps of the software's analysis workflow. Even when the cytoplasm is hazy, several micronuclei are joined to each other, or micronuclei are attached to the nucleus, this algorithm can swiftly and efficiently detect binucleated cells and micronuclei in a verification of 2000 images. In a test of 20 slides, the software reached a detection rate of 99.4% of manual detection in terms of binucleated cells, with a false positive rate of 14.7%. In terms of micronuclei detection, the software reached a detection rate of 115.1% of manual detection, with a 26.2% false positive rate. Each image analysis takes roughly 0.3 s, which is an order of magnitude faster than manual detection.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Linfocitos , Algoritmos , Citocinesis , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Micronúcleos con Defecto Cromosómico , Pruebas de Micronúcleos/métodos
3.
Acta Pharm Sin B ; 10(6): 1020-1035, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32642409

RESUMEN

Although the tumor suppressor P53 is known to regulate a broad network of signaling pathways, it is still unclear how certain drugs influence these P53 signaling networks. Here, we used a comprehensive single-cell multiomics view of the effects of ginsenosides on cancer cells. Transcriptome and proteome profiling revealed that the antitumor activity of ginsenosides is closely associated with P53 protein. A miRNA-proteome interaction network revealed that P53 controlled the transcription of at least 38 proteins, and proteome-metabolome profiling analysis revealed that P53 regulated proteins involved in nucleotide metabolism, amino acid metabolism and "Warburg effect". The results of integrative multiomics analysis revealed P53 protein as a potential key target that influences the anti-tumor activity of ginsenosides. Furthermore, by applying affinity mass spectrometry (MS) screening and surface plasmon resonance fragment library screening, we confirmed that 20(S)-protopanaxatriol directly targeted adjacent regions of the P53 DNA-binding pocket and promoted the stability of P53-DNA interactions, which further induced a series of omics changes.

4.
J Proteome Res ; 18(5): 2100-2108, 2019 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-30860844

RESUMEN

Ginsenosides have previously been demonstrated to effectively inhibit cancer cell growth and survival in both animal models and cell lines. However, the specific ginsenoside component that is the active ingredient for cancer treatment through interaction with a target protein remains unknown. By an integrated quantitative proteomics approach via affinity mass spectrum (MS) technology, we deciphered the core structure of the ginsenoside active ingredient derived from crude extracts of ginsenosides and progressed toward identifying the target protein that mediates its anticancer activity. The Tandem Mass Tag (TMT) labeling quantitative proteomics technique acquired 55620 MS/MS spectra that identified 5499 proteins and 3045 modified proteins. Of these identified proteins, 224 differentially expressed proteins and modified proteins were significantly altered in nonsmall cell lung cancer cell lines. Bioinformatics tools for comprehensive analysis revealed that the Ras protein played a general regulatory role in many functional pathways and was probably the direct target protein of a compound in ginsenosides. Then, affinity MS screening based on the Ras protein identified 20(s)-protopanaxadiol, 20(s)-Ginsenoside Rh2, and 20(s)-Ginsenoside Rg3 had affinity with Ras protein under different conditions. In particular, 20(s)-protopanaxadiol, whose derivatives are the reported antitumor compounds 20(s)-Ginsenoside Rh2 and 20(s)-Ginsenoside Rg3 that have a higher affinity for Ras via a low KD of 1.22 µM and the mutation sites of G12 and G60, was demonstrated to play a core role in those interactions. Moreover, the molecular mechanism and bioactivity assessment results confirmed the identity of the chemical ligand that was directly acting on the GTP binding pocket of Ras and shown to be effective in cancer cell bioactivity profiles.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Ginsenósidos/farmacología , Proteínas de Neoplasias/antagonistas & inhibidores , Sapogeninas/farmacología , Proteínas ras/antagonistas & inhibidores , Animales , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ginsenósidos/química , Ginsenósidos/aislamiento & purificación , Guanosina Trifosfato/química , Guanosina Trifosfato/metabolismo , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Simulación del Acoplamiento Molecular , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Unión Proteica/efectos de los fármacos , Conformación Proteica , Proteómica/métodos , Sapogeninas/química , Sapogeninas/aislamiento & purificación , Proteínas ras/química , Proteínas ras/genética , Proteínas ras/metabolismo
5.
J Biol Chem ; 293(45): 17430-17441, 2018 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-30237164

RESUMEN

Phosphoinositide phospholipases C (PLCs) are a family of eukaryotic intracellular enzymes with important roles in signal transduction. In addition to their location at the plasma membrane, PLCs also exist within the cell nucleus where they are stored. We previously demonstrated that OSBP-related protein 4L (ORP4L) anchors cluster of differentiation 3ϵ (CD3ϵ) to the heterotrimeric G protein subunit (Gαq/11) to control PLCß3 relocation and activation. However, the underlying mechanism by which ORP4L facilitates PLCß3 translocation remains unknown. Here, using confocal immunofluorescence microscopy and coimmunoprecipitation assays, we report that ORP4L stimulates PLCß3 translocation from the nucleus to the plasma membrane in Jurkat T-cells in two steps. First, we found that ORP4L is required for the activation of Ras-related nuclear protein (RAN), a GTP-binding nuclear protein that binds to exportin 1 and eventually promotes the nuclear export of PLCß3. Second, we also observed that ORP4L interacts with vesicle-associated membrane protein-associated protein A (VAPA) through its two phenylalanines in an acidic tract (FFAT) motif. This complex enabled PLCß3 movement to the plasma membrane, indicating that PLCß3 translocation occurs in a VAPA-dependent manner. This study reveals detailed mechanistic insight into the role of ORP4L in PLCß3 redistribution from storage within the nucleus to the plasma membrane via RAN activation and interaction with VAPA in Jurkat T-cells.


Asunto(s)
Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Fosfolipasa C beta/metabolismo , Receptores de Esteroides/metabolismo , Linfocitos T/metabolismo , Transporte Activo de Núcleo Celular/fisiología , Membrana Celular/genética , Núcleo Celular/genética , Subunidades alfa de la Proteína de Unión al GTP/genética , Subunidades alfa de la Proteína de Unión al GTP/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/genética , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/metabolismo , Células HeLa , Células Hep G2 , Humanos , Células Jurkat , Células K562 , Fosfolipasa C beta/genética , Receptores de Esteroides/genética , Linfocitos T/citología , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo , Proteína de Unión al GTP ran/genética , Proteína de Unión al GTP ran/metabolismo
6.
Circ Res ; 119(12): 1296-1312, 2016 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-27729467

RESUMEN

RATIONALE: Macrophage survival within the arterial wall is a central factor contributing to atherogenesis. Oxysterols, major components of oxidized low-density lipoprotein, exert cytotoxic effects on macrophages. OBJECTIVE: To determine whether oxysterol-binding protein-related protein 4 L (ORP4L), an oxysterol-binding protein, affects macrophage survival and the pathogenesis of atherosclerosis. METHODS AND RESULTS: By hiring cell biological approaches and ORP4L-/- mice, we show that ORP4L coexpresses with and forms a complex with Gαq/11 and phospholipase C (PLC)-ß3 in macrophages. ORP4L facilitates G-protein-coupled ligand-induced PLCß3 activation, IP3 production, and Ca2+ release from the endoplasmic reticulum. Through this mechanism, ORP4L sustains antiapoptotic Bcl-XL expression through Ca2+-mediated c-AMP responsive element binding protein transcriptional regulation and thus protects macrophages from apoptosis. Excessive stimulation with the oxysterol 25-hydroxycholesterol disassembles the ORP4L/Gαq/11/PLCß3 complexes, resulting in reduced PLCß3 activity, IP3 production, and Ca2+ release, as well as decreased Bcl-XL expression and increased apoptosis. Overexpression of ORP4L counteracts these oxysterol-induced defects. Mice lacking ORP4L exhibit increased apoptosis of macrophages in atherosclerotic lesions and a reduced lesion size. CONCLUSIONS: ORP4L is crucial for macrophage survival. It counteracts the cytotoxicity of oxysterols/oxidized low-density lipoprotein to protect macrophage from apoptosis, thus playing an important role in the development of atherosclerosis.


Asunto(s)
Aterosclerosis/metabolismo , Aterosclerosis/prevención & control , Macrófagos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Esteroides/metabolismo , Transducción de Señal/fisiología , Animales , Aterosclerosis/patología , Supervivencia Celular/fisiología , Células Cultivadas , Humanos , Macrófagos/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados
7.
PLoS One ; 11(7): e0159115, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27438131

RESUMEN

BACKGROUND AND OBJECTIVES: MicroRNA (miR)-143/145, known as tumor suppressors, can promote cell apoptosis and differentiation, and suppress cell proliferation, invasion and migration. We performed a case-control study to investigate the association of rs353293 in the promoter region of miR-143/145 with bladder cancer risk. METHODS: In total, 869 subjects including 333 cases and 536 controls were enrolled in this study, and the rs353293 polymorphism was genotyped by using a Taqman assay. The promoter activity was measured by the Dual-Luciferase Assay System. RESULTS: We calculated an adjusted odds ratio of 0.64 for the presence of either AA/AG genotypes (95% CI 0.46-0.90) and 0.64 (95% CI 0.47-0.87) for carrying at least one A allele in bladder cancer. Stratified analyses showed that the AA/AG genotypes and the A allele were less prevalent in patients with low grade tumors, compared to those harboring higher grade bladder cancers (adjusted OR = 0.53, 95% CI, 0.30-0.94, P = 0.03 and adjusted OR = 0.54, 95% CI, 0.32-0.92, P = 0.02, respectively). In vitro luciferase reporter analysis showed that rs353293A allele had a lower activity compared with the rs353293G allele (P < 0.001). CONCLUSION: These findings suggest that the functional rs353293 polymorphism may be a useful biomarker to predict the risk of bladder cancer.


Asunto(s)
Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , MicroARNs/genética , Polimorfismo de Nucleótido Simple/genética , Regiones Promotoras Genéticas , Neoplasias de la Vejiga Urinaria/genética , Línea Celular Tumoral , Femenino , Humanos , Masculino , MicroARNs/metabolismo , Persona de Mediana Edad , Factores de Riesgo , Transcripción Genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA