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1.
J Food Drug Anal ; 31(1): 55-72, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-37224555

RESUMO

Glycidyl esters (GEs) and 2- and 3-monochloropropanediol esters (MCPDEs) are emerging process-generated food contaminants known as possible carcinogens. Herein, a direct method is developed and validated for the first time to simultaneously quantify seven GEs and twenty-four MCPDE congeners of processed foods using liquid chromatography-tandem mass spectrometry in a single sequence without ester cleavage or derivatisation, thereby allowing for the simultaneous analysis of numerous food matrices with high accuracy and precision. Our results show levels of GEs varying from

Assuntos
Alimentos , Espectrometria de Massas em Tandem , Cromatografia Líquida , Ésteres
2.
Dentomaxillofac Radiol ; 51(3): 20210341, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34788124

RESUMO

OBJECTIVES: This study aimed to develop models that can automatically detect anterior disc displacement (ADD) of the temporomandibular joint (TMJ) on MRIs before orthodontic treatment to reduce the risk of developing serious complications after treatment. METHODS: We used 9009 sagittal MRI of the TMJ as input and constructed three sets of deep learning models to detect ADD automatically. Deep learning models were developed using a convolutional neural network (CNN) based on the ResNet architecture and the "Imagenet" database. Five-fold cross-validation, oversampling, and data augmentation techniques were applied to reduce the risk of overfitting the model. The accuracy and area under the curve (AUC) of the three models were compared. RESULTS: The performance of the maximum open mouth position model was excellent with accuracy and AUC of 0.970 (±0.007) and 0.990 (±0.005), respectively. For closed mouth position models, the accuracy and AUC of diagnostic Criteria 1 were 0.863 (±0.008) and 0.922 (±0.009), respectively significantly higher than that of diagnostic Criteria 2 with 0.839 (±0.013) (p = 0.009) and AUC of 0.885 (±0.018) (p = 0.003). The classification activation heat map also improved our understanding of the models and visually displayed the areas that play a key role in the model recognition process. CONCLUSION: Our CNN model resulted in high accuracy and AUC in detecting ADD and can therefore potentially be used by clinicians to assess ADD before orthodontic treatment, and hence improve treatment outcomes.


Assuntos
Aprendizado Profundo , Disco da Articulação Temporomandibular , Algoritmos , Humanos , Imageamento por Ressonância Magnética/métodos , Articulação Temporomandibular , Disco da Articulação Temporomandibular/diagnóstico por imagem
3.
Cell Rep Methods ; 1(7)2021 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-34888542

RESUMO

MOTIVATION: Quantitative studies of cellular morphodynamics rely on extracting leading-edge velocity time series based on accurate cell segmentation from live cell imaging. However, live cell imaging has numerous challenging issues regarding accurate edge localization. Fluorescence live cell imaging produces noisy and low-contrast images due to phototoxicity and photobleaching. While phase contrast microscopy is gentle to live cells, it suffers from the halo and shade-off artifacts that cannot be handled by conventional segmentation algorithms. Here, we present a deep learning-based pipeline, termed MARS-Net (Multiple-microscopy-type-based Accurate and Robust Segmentation Network), that utilizes transfer learning and data from multiple types of microscopy to localize cell edges with high accuracy, allowing quantitative profiling of cellular morphodynamics. SUMMARY: To accurately segment cell edges and quantify cellular morphodynamics from live-cell imaging data, we developed a deep learning-based pipeline termed MARS-Net (multiple-microscopy-type-based accurate and robust segmentation network). MARS-Net utilizes transfer learning and data from multiple types of microscopy to localize cell edges with high accuracy. For effective training on distinct types of live-cell microscopy, MARS-Net comprises a pretrained VGG19 encoder with U-Net decoder and dropout layers. We trained MARS-Net on movies from phase-contrast, spinning-disk confocal, and total internal reflection fluorescence microscopes. MARS-Net produced more accurate edge localization than the neural network models trained with single-microscopy-type datasets. We expect that MARS-Net can accelerate the studies of cellular morphodynamics by providing accurate pixel-level segmentation of complex live-cell datasets.


Assuntos
Aprendizado Profundo , Microscopia , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Algoritmos
4.
Sci Rep ; 11(1): 23285, 2021 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-34857846

RESUMO

Machine learning approaches have shown great promise in biology and medicine discovering hidden information to further understand complex biological and pathological processes. In this study, we developed a deep learning-based machine learning algorithm to meaningfully process image data and facilitate studies in vascular biology and pathology. Vascular injury and atherosclerosis are characterized by neointima formation caused by the aberrant accumulation and proliferation of vascular smooth muscle cells (VSMCs) within the vessel wall. Understanding how to control VSMC behaviors would promote the development of therapeutic targets to treat vascular diseases. However, the response to drug treatments among VSMCs with the same diseased vascular condition is often heterogeneous. Here, to identify the heterogeneous responses of drug treatments, we created an in vitro experimental model system using VSMC spheroids and developed a machine learning-based computational method called HETEROID (heterogeneous spheroid). First, we established a VSMC spheroid model that mimics neointima-like formation and the structure of arteries. Then, to identify the morphological subpopulations of drug-treated VSMC spheroids, we used a machine learning framework that combines deep learning-based spheroid segmentation and morphological clustering analysis. Our machine learning approach successfully showed that FAK, Rac, Rho, and Cdc42 inhibitors differentially affect spheroid morphology, suggesting that multiple drug responses of VSMC spheroid formation exist. Overall, our HETEROID pipeline enables detailed quantitative drug characterization of morphological changes in neointima formation, that occurs in vivo, by single-spheroid analysis.


Assuntos
Aprendizado de Máquina , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/patologia , Aterosclerose/patologia , Células Cultivadas , Quinase 1 de Adesão Focal/antagonistas & inibidores , Quinase 1 de Adesão Focal/fisiologia , Humanos , Neointima/patologia , Esferoides Celulares/fisiologia , Lesões do Sistema Vascular/patologia , Proteína cdc42 de Ligação ao GTP/antagonistas & inibidores , Proteína cdc42 de Ligação ao GTP/fisiologia , Proteínas rac de Ligação ao GTP/antagonistas & inibidores , Proteínas rac de Ligação ao GTP/fisiologia
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