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1.
J Digit Imaging ; 36(2): 617-626, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36478311

RESUMO

Detecting and identifying malignant nodules on chest computed tomography (CT) plays an important role in the early diagnosis and timely treatment of lung cancer, which can greatly reduce the number of deaths worldwide. In view of the existing methods in pulmonary nodule diagnosis, the importance of clinical radiological structured data (laboratory examination, radiological data) is ignored for the accuracy judgment of patients' condition. Hence, a multi-modal fusion multi-branch classification network is constructed to detect and classify pulmonary nodules in this work: (1) Radiological data of pulmonary nodules are used to construct structured features of length 9. (2) A multi-branch fusion-based effective attention mechanism network is designed for 3D CT Patch unstructured data, which uses 3D ECA-ResNet to dynamically adjust the extracted features. In addition, feature maps with different receptive fields from multi-layer are fully fused to obtain representative multi-scale unstructured features. (3) Multi-modal feature fusion of structured data and unstructured data is performed to distinguish benign and malignant nodules. Numerous experimental results show that this advanced network can effectively classify the benign and malignant pulmonary nodules for clinical diagnosis, which achieves the highest accuracy (94.89%), sensitivity (94.91%), and F1-score (94.65%) and lowest false positive rate (5.55%).


Assuntos
Neoplasias Pulmonares , Nódulos Pulmonares Múltiplos , Nódulo Pulmonar Solitário , Humanos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Nódulo Pulmonar Solitário/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Imageamento Tridimensional/métodos , Tomografia Computadorizada por Raios X/métodos
2.
Int J Comput Assist Radiol Surg ; 16(12): 2269-2277, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34449037

RESUMO

PURPOSE: Considering that false-positive and true pulmonary nodules are highly similar in shapes and sizes between lung computed tomography scans, we develop and evaluate a false-positive nodules reduction method applied to the computer-aided diagnosis system. METHODS: To improve the pulmonary nodule diagnosis quality, a 3D convolutional neural networks (CNN) model is constructed to effectively extract spatial information of candidate nodule features through the hierarchical architecture. Furthermore, three paths corresponding to three receptive field sizes are adopted and concatenated in the network model, so that the feature information is fully extracted and fused to actively adapting to the changes in shapes, sizes, and contextual information between pulmonary nodules. In this way, the false-positive reduction is well implemented in pulmonary nodule detection. RESULTS: Multi-path 3D CNN is performed on LUNA16 dataset, which achieves an average competitive performance metric score of 0.881, and excellent sensitivity of 0.952 and 0.962 occurs to 4, 8 FP/Scans. CONCLUSION: By constructing a multi-path 3D CNN to fully extract candidate target features, it accurately identifies pulmonary nodules with different sizes, shapes, and background information. In addition, the proposed general framework is also suitable for similar 3D medical image classification tasks.


Assuntos
Neoplasias Pulmonares , Nódulo Pulmonar Solitário , Diagnóstico por Computador , Humanos , Imageamento Tridimensional , Neoplasias Pulmonares/diagnóstico por imagem , Redes Neurais de Computação , Interpretação de Imagem Radiográfica Assistida por Computador , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X
3.
Huan Jing Ke Xue ; 42(7): 3166-3175, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212642

RESUMO

Microplastics have been found in many environmental media such as sea water, coastal tidal flats, terrestrial water, sediments, and organisms. Microplastics pollution in inland freshwater lakes have received extensive attention; however, the correlation between eutrophication and microplastics pollution in freshwater lakes remains unclear. In this study, 24 sampling sites were set up in the near shore surface waters of Dianchi Lake, and the pollution characteristics of microplastics such as abundance, composition, particle size, color, and form were evaluated. Water quality parameters related to eutrophication state were analyzed, and the eutrophication indices were further calculated. Specifically, sample pre-treatment was conducted according to the method issued by National Oceanic and Atmospheric Administration (NOAA) of the United States. The color and morphological characteristics of microplastic samples were observed using a stereoscopic microscope, and counts and particle size measurements were performed using Nano Measure 1.2 software. Parts of the samples were selected, and the polymer composition analysis was performed using micro-Fourier Transform infrared (µ-FTIR) spectroscopy. The indices related to eutrophication level evaluation were tested according to the experimental standard methods issued by the Ministry of Ecology and Environment of China. The results showed that the abundance of microplastics in the near shore waters of Dianchi Lake was between 800 and 6000 n·m-3, with an average value of 2867 n·m-3. The types of polymers detected were polyethylene terephthalate (PET), polyetherurethane (PEU), polypropylene (PP), polyethylene (PE), and polyvinyl acetate (PVAc), respectively. The diameter proportion of microplastics in the range of 0.2-0.5 mm was the highest. Fiber microplastics accounted for the most observed type, followed by fragments and films. Among the 24 monitoring sites, it was found that proportions of severe, moderate, and mild eutrophication and mesotrophication sites accounted for 8.33%, 58.33%, 29.17%, and 4.17% of the total sampling sites, respectively, and the main pollutant was total nitrogen (TN). Microplastics abundances in the near shore waters of Dianchi Lake were significantly positively correlated with TN concentrations (P<0.01), whereas they were negatively correlated with chlorophyll a(Chl-a)concentrations, not reaching a significant level (P>0.05). The microplastics abundance and TN concentrations in the north bank water near the main urban area of Kunming were significantly higher than those in the other three banks. Microplastics and TN were considered to potentially have the same origin and be attributed to the tail water discharge from WWTPs.


Assuntos
Microplásticos , Poluentes Químicos da Água , China , Clorofila A , Monitoramento Ambiental , Eutrofização , Sedimentos Geológicos , Lagos/análise , Plásticos , Poluentes Químicos da Água/análise
4.
Comput Methods Programs Biomed ; 155: 179-187, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29512497

RESUMO

BACKGROUND AND OBJECTIVES: Tight junction proteins are correlated with cancer development. As the pivotal proteins in epithelial cells, altered expression and distribution of different claudins have been reported in a wide variety of human malignancies. We have previously reported that claudin-7 was strongly expressed in benign bronchial epithelial cells at the cell-cell junction while expression of claudin-7 was either altered with discontinued weak expression or completely absent in lung cancers. Based on these results, we continued working on the expression pattern of claudin-7 and its relationship with lung cancer development. We herein proposed a new Digital Image Classification, Fragmentation index, Morphological analysis (DICFM) method for differentiating the normal lung tissues and lung cancer tissues based on the claudin-7 immunohistochemical staining. METHODS: Seventy-seven lung cancer samples were obtained from the Second Affiliated Hospital of Zhejiang University and claudin-7 immunohistochemical staining was performed. Based on C++ and Open Source Computer Vision Library (OpenCV, version 2.4.4), the DICFM processing module was developed. Intensity and fragmentation of claudin-7 expression, as well as the morphological parameters of nuclei were calculated. Evaluation of results was performed using Receiver Operator Characteristic (ROC) analysis. RESULTS: Agreement between these computational results and the results obtained by two pathologists was demonstrated. The intensity of claudin-7 expression was significantly decreased while the fragmentation was significantly increased in the lung cancer tissues compared to the normal lung tissues and the intensity was strongly positively associated with the differentiation of lung cancer cells. Moreover, the perimeters of the nuclei of lung cancer cells were significantly greater than that of the normal lung cells, while the parameters of area and circularity revealed no statistical significance. CONCLUSIONS: Taken together, our DICFM approach may be applied as an appropriate approach to quantify the immunohistochemical staining of claudin-7 on the cell membrane and claudin-7 may serve as a marker for identification of lung cancer.


Assuntos
Claudinas/metabolismo , Processamento de Imagem Assistida por Computador , Neoplasias Pulmonares/metabolismo , Automação , Biomarcadores Tumorais/metabolismo , Western Blotting , Membrana Celular/metabolismo , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/classificação , Prognóstico
5.
Cell Immunol ; 318: 23-28, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28601359

RESUMO

Osteopontin (OPN) is a multifunctional protein involved in various pathophysiological processes. However, the role of OPN in Pseudomonas aeruginosa-related sepsis is not yet clear. Here, we found that OPN expression was elevated in plasma and spleen samples from P. aeruginosa-infected mice. To determine the function of OPN in sepsis, we used wild-type (WT) and OPN-knockout (KO) mice with P. aeruginosa-induced bacteremia. We found that OPN-KO mice exhibited reduced mortality compared with WT mice and that OPN exacerbated spleen bleeding and functional impairment. OPN-KO mice exhibited reduced secretion of pro-inflammatory cytokines, such as interferon-γ, interleukin (IL)-1ß, IL-12, and tumor necrosis factor-α, whereas levels of anti-inflammatory cytokine IL-10 and the leukocyte trafficking mediator macrophage inflammatory protein (MIP)-2 were not altered. Additionally, the percentages and absolute numbers of B cells were elevated in the spleens of OPN-KO mice. Thus, OPN promoted sepsis in P. aeruginosa-infected mice and potentially blocked B cell-dependent immunity.


Assuntos
Linfócitos B/imunologia , Bacteriemia/imunologia , Osteopontina/metabolismo , Infecções por Pseudomonas/imunologia , Pseudomonas aeruginosa/imunologia , Baço/fisiologia , Animais , Carga Bacteriana , Células Cultivadas , Citocinas/metabolismo , Humanos , Mediadores da Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteopontina/genética
6.
Biosci Biotechnol Biochem ; 74(2): 322-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20139613

RESUMO

Artemisia sacrorum Ledeb. (Compositae) (ASL) is a traditional Chinese medicine used to treat different hepatic diseases. However, a hypolipidemic effect of ASL on fatty liver disease has not been reported. Therefore, we investigated whether 95% ethanol eluate (EE), an active part of ASL, would attenuate hepatic lipid accumulation in human HepG2 cells by activating AMP-activated protein kinase (AMPK). Significant decreases in triglyceride levels and increases in AMPK and acetyl-CoA carboxylase (ACC) phosphorylation were observed when the cells were treated with 95% EE. EE down-regulated the lipogenesis gene expression of sterol regulatory element-binding protein 1c (SREBP1c) and its target genes, such as fatty acid synthase (FAS) and stearoyl-CoA desaturase 1 (SCD1), in a time- and dose-dependent manner. In contrast, the lipolytic gene expression of peroxisome proliferator-activated receptor alpha (PPAR-alpha) and CD36 increased in a time- and dose-dependent manner. These effects were abolished by pretreatment with compound C, an AMPK inhibitor. However, there were no differences in the gene expression of SREBP2, low density lipoprotein receptor (LDLR), hydroxymethyl glutaryl CoA reductase (HMG-CoA), or glucose transporter 2 (GLUT2). At the same time, 95% EE significantly increased the gene expression of acyl CoA oxidase (ACOX) in a time- and dose-dependent manner. Thus, AMPK mediated 95% EE induced suppression of SREBP1c and activation of PPAR-alpha respectively. These finding indicate that 95% EE attenuates hepatic lipid accumulation through AMPK activation and may be active in the prevention of serious diseases such as fatty liver, obesity, and type-2 diabetic mellitus.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Artemisia/genética , Artemisia/metabolismo , Lipogênese/genética , Fígado/metabolismo , Ativação Enzimática , Células Hep G2 , Humanos
7.
Plant Physiol Biochem ; 43(6): 535-47, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15922610

RESUMO

Phospholipase D alpha (PLD, EC 3.1.4.4)) is a key enzyme involved in membrane deterioration that occurs during fruit ripening and senescence. The biochemical and molecular characteristics of PLD was studied in strawberry (Fragaria ananassa Duch) fruits, which are non-climacteric fruits. PLD activity was primarily associated with the mitochondrial and microsomal fractions and showed increased activity during development. Optimal pH levels of activity were observed at 5.5 and 6.5 for mitochondrial PLD and at 5 and 7 for microsomal PLD. Calcium enhanced microsomal PLD activity at 1-40 microM levels. PLD activity followed Michaelis-Menten kinetics. Lineweaver-Burk analysis gave Km values in the range of 114 and 277 microM using dipalmitoylphosphatidylcholine (DPPC) as substrate for mitochondrial and microsomal PLD, respectively. The Vmax value for the microsomal PLD was nearly 12-fold higher than that of mitochondrial PLD. A 2874 bp full-length cDNA for PLD alpha was amplified from strawberry fruit mRNA using RT-PCR and 5'- and 3'-RACE encoding an 810 amino acid-polypeptide. The predicted strawberry PLD sequence showed the characteristic C2 domain and the phospholipase domains conferring calcium sensitivity and the enzyme activity, respectively. The strawberry PLD alpha showed a high degree of similarity to other PLD alphas from plants. The implications of PLD regulation during ripening of fruits are discussed.


Assuntos
Fragaria/enzimologia , Microssomos/enzimologia , Mitocôndrias/enzimologia , Fosfolipase D/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , DNA Complementar , Ativação Enzimática , Fragaria/crescimento & desenvolvimento , Fragaria/ultraestrutura , Frutas/enzimologia , Frutas/crescimento & desenvolvimento , Frutas/ultraestrutura , Regulação da Expressão Gênica de Plantas , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Fosfolipase D/genética , Fosfolipase D/isolamento & purificação , Estrutura Secundária de Proteína , Homologia de Sequência de Aminoácidos
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