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1.
Comput Biol Med ; 164: 107215, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37481947

RESUMEN

Glaucoma is a leading cause of worldwide blindness and visual impairment, making early screening and diagnosis is crucial to prevent vision loss. Cup-to-Disk Ratio (CDR) evaluation serves as a widely applied approach for effective glaucoma screening. At present, deep learning methods have exhibited outstanding performance in optic disk (OD) and optic cup (OC) segmentation and maturely deployed in CAD system. However, owning to the complexity of clinical data, these techniques could be constrained. Therefore, an original Coarse-to-Fine Transformer Network (C2FTFNet) is designed to segment OD and OC jointly , which is composed of two stages. In the coarse stage, to eliminate the effects of irrelevant organization on the segmented OC and OD regions, we employ U-Net and Circular Hough Transform (CHT) to segment the Region of Interest (ROI) of OD. Meanwhile, a TransUnet3+ model is designed in the fine segmentation stage to extract the OC and OD regions more accurately from ROI. In this model, to alleviate the limitation of the receptive field caused by traditional convolutional methods, a Transformer module is introduced into the backbone to capture long-distance dependent features for retaining more global information. Then, a Multi-Scale Dense Skip Connection (MSDC) module is proposed to fuse the low-level and high-level features from different layers for reducing the semantic gap among different level features. Comprehensive experiments conducted on DRIONS-DB, Drishti-GS, and REFUGE datasets validate the superior effectiveness of the proposed C2FTFNet compared to existing state-of-the-art approaches.


Asunto(s)
Glaucoma , Disco Óptico , Humanos , Disco Óptico/diagnóstico por imagen , Glaucoma/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador/métodos , Técnicas de Diagnóstico Oftalmológico , Tamizaje Masivo , Fondo de Ojo , Procesamiento de Imagen Asistido por Computador/métodos
2.
Huan Jing Ke Xue ; 42(6): 3018-3027, 2021 Jun 08.
Artículo en Chino | MEDLINE | ID: mdl-34032102

RESUMEN

To ascertain the impact of mercury mining on the surrounding soil environment and human health, 42 surface soil composite samples were collected around a mercury mining area in Youyang County, Chongqing, and the heavy metals (Cd, Hg, Pb, As, Cr, Cu, Zn, and Ni) contents and pH of the soil, the spatial distribution of heavy metals, pollution degree, and ecological risk were studied. The results show that the surface soil layer in the study area is significantly enriched in heavy metals. According to the soil environmental quality risk control standard for soil contamination of agricultural land (GB15618-2018), soil Cd, Hg, Pb, As, and Zn showed different degrees of excess. A certain degree of pollution and ecological risk was also identified in the studied soil. Moderate-to-severe pollution and strong ecological risk areas are distributed around the mining sites, indicating the impact of mining activities on the soil environment. The content of Cr, Cu, and Ni in the soil may be affected by weathering and soil formation from the parent rock; Hg, Pb, and Zn content may be affected by human activities such as mineral mining; and Cd and As content may be affected by both geological processes and human activities. Heavy metals pose less of a health risk for adults but have a greater probability of causing health risks for children. Soil As is the main contributor to human health risks, and the oral intake of the eight heavy metals has the highest contribution rate. The mining of mercury is the main cause of soil pollution and ecological risk in the study area.


Asunto(s)
Mercurio , Metales Pesados , Contaminantes del Suelo , Niño , China , Monitoreo del Ambiente , Contaminación Ambiental/análisis , Humanos , Mercurio/análisis , Metales Pesados/análisis , Minería , Medición de Riesgo , Suelo , Contaminantes del Suelo/análisis
3.
Free Radic Biol Med ; 169: 361-381, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33762162

RESUMEN

Long noncoding RNAs (lncRNAs) are important regulators in various diseases including diabetic retinopathy (DR). In this study, DR patients exhibited significantly increased expression of serum LncRNA-OGRU compared with normal individuals. Streptozotocin (STZ)-challenged rats with DR also had higher OGRU expression in retinas than that of the control group, which was confirmed in Müller cells upon high glucose (HG) stimulation. OGRU knockdown remarkably decreased vascular endothelial growth factor (VEGF) and transforming growth factor-ß1 (TGF-ß1) expression in HG-incubated Müller cells. HG-induced inflammatory response and oxidative stress in vitro were markedly mitigated by OGRU knockdown through restraining IκBɑ/nuclear factor kappa beta (NF-κB) and improving nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathways, respectively. Further studies indicated that OGRU suppression greatly restored miR-320 expression, and a negative correlation between them was detected in DR patients. We also found that miR-320 over-expression considerably restrained TGF-ß1 signaling, and hindered inflammation and reactive oxygen species (ROS) production in HG-stimulated Müller cells. Additionally, OGRU knockdown or miR-320 over-expression could dramatically down-regulate ubiquitin-specific peptidase 14 (USP14) expression levels in HG-incubated Müller cells, and miR-320 could directly target USP14. Notably, OGRU/miR-320 axis-mediated TGF-ß1 signaling, inflammation and ROS were largely dependent on USP14. Intriguingly, our results showed that USP14 directly interacted with transforming growth factor-beta type 1 receptor (TßR1), and impeded TßR1 ubiquitination and degradation. Furthermore, USP14 could also facilitate IκBɑ deubiquitination and degradation, exacerbating IκBɑ phosphorylation and NF-κB activation. Finally, our in vivo studies confirmed that OGRU knockdown considerably ameliorated DR progression in STZ-challenged rats through mediating the mechanisms observed in vitro. Collectively, these findings implicated that LncRNA-OGRU mediated DR progression through competing for miR-320 to regulate USP14 expression, and thus LncRNA-OGRU/miR-320/USP14 axis may be considered as a therapeutic target for DR treatment.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , MicroARNs , ARN Largo no Codificante , Animales , Retinopatía Diabética/genética , Humanos , Inflamación/genética , MicroARNs/genética , MicroARNs/metabolismo , Estrés Oxidativo/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Ratas , Ubiquitina Tiolesterasa/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo
4.
Huan Jing Ke Xue ; 41(10): 4749-4756, 2020 Oct 08.
Artículo en Chino | MEDLINE | ID: mdl-33124409

RESUMEN

To investigate the impact of mining activities and geological background on the soil environment, 156 soil samples were collected from an agricultural land in southern Youyang County, Chongqing. The content and pH of heavy metals in the soil were analyzed, and the Nemerow index method was used to evaluate the pollution status of soil heavy metals. The source of soil heavy metals was discussed using the principal component analysis/absolute principal component score (PCA/APCS) receptor model. The results showed that the soil Cd pollution was distributed in a planar shape, while soil Hg mainly appeared as point pollution. The medium-severe soil pollution was mainly distributed at the junction of Tushi Town, Mawang Town, and Longtan Town, where the soil was predominantly acidic and there was a higher risk of crop contamination; the indicator Kriging evaluation results showed that there was a higher probability of soil contamination at the junction of the three towns and the northern part of Tushi Township. The results of the PCA/APCS receptor model analysis showed that the sources of soil As, Cd, Cr, and Ni were mainly controlled by geological background; soil Hg, Pb, and Zn were mainly controlled by mining activities; further, soil Cu was affected by both geological background and mining activities. In addition, the agricultural activities were also one of the sources of soil As, Cd, Pb, Cu, and Zn. The medium-heavy pollution of the soil in the study area was mainly caused by mining activities, while the heavy metal pollution of the soil caused by geological background was mainly light pollution. This study can provide a theoretical basis for the safe use of land and the prevention and control of soil pollution in typical regions.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , China , Monitoreo del Ambiente , Contaminación Ambiental/análisis , Granjas , Metales Pesados/análisis , Medición de Riesgo , Suelo , Contaminantes del Suelo/análisis
5.
Front Chem ; 8: 105, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32154218

RESUMEN

As one of the most promising fast energy storage devices, supercapacitor has been attracting intense attention for many emerging applications. However, how to enhance the electrochemical performance of electrode materials is still the main issue among various researches. In this paper, hierarchical porous carbons derived from Eleocharis dulcis has been prepared by chemical activation process with the aid of KOH at elevated temperature. Results show that the N, P co-doped porous carbon exhibits excellent electrochemical performance, it owns a specific capacitance of 340.2 F/g at 1 A/g, and obtains outstanding cycling stability of 96.9% of capacitance retention at 10 A/g after 5,000 cycles in a three-electrode system. Moreover, in the two-electrode system, the product still maintains a high specific capacitance of 227.2 F/g at 1 A/g, and achieves good electrochemical cycle stability (94.2% of capacitance retention at 10 A/g after 10,000 cycles); besides, its power/energy density are 3694.084 and 26.289 Wh/kg, respectively. Therefore, the combination of facile synthesis strategy and excellent electrochemical performance makes Eleocharis dulcis-based porous carbon as a promising electrode material for supercapacitor.

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