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1.
Anal Bioanal Chem ; 415(17): 3449-3462, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37195443

RESUMO

Early, express, and reliable detection of cancer can provide a favorable prognosis and decrease mortality. Tumor biomarkers have been proven to be closely related to tumor occurrence and development. Conventional tumor biomarker detection based on genomic, proteomic, and metabolomic methods is time and equipment-consuming and always needs a specific target marker. Surface-enhanced Raman scattering (SERS), as a non-invasive ultrasensitive and label-free vibrational spectroscopy technique, can detect cancer-related biomedical changes in biofluids. In this paper, 110 serum samples were collected from 30 healthy controls and 80 cancer patients (including 30 bladder cancer (BC), 30 adrenal cancer (AC), and 20 acute myeloid leukemia (AML)). One microliter of blood serum was mixed with 1 µl silver colloid and then was air-dried for SERS measurements. After spectral data augmentation, one-dimensional convolutional neural network (1D-CNN) was proposed for precise and rapid identification of healthy and three different cancers with high accuracy of 98.27%. After gradient-weighted class activation mapping (Grad-CAM) based spectral interpretation, the contributions of SERS peaks corresponding to biochemical substances indicated the most potential biomarkers, i.e., L-tyrosine in bladder cancer; acetoacetate and riboflavin in adrenal cancer and phospholipids, amide-I, and α-Helix in acute myeloid leukemia, which might provide an insight into the mechanism of intelligent diagnosis of different cancers based on label-free serum SERS. The integration of label-free SERS and deep learning has great potential for the rapid, reliable, and non-invasive detection of cancers, which may significantly improve the precise diagnosis in clinical practice.


Assuntos
Neoplasias das Glândulas Suprarrenais , Aprendizado Profundo , Neoplasias da Bexiga Urinária , Humanos , Proteômica , Neoplasias da Bexiga Urinária/diagnóstico , Biomarcadores Tumorais , Análise Espectral Raman
2.
J Xray Sci Technol ; 31(5): 935-949, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37393485

RESUMO

BACKGROUND: C-arm fluoroscopy, as an effective diagnosis and treatment method for spine surgery, can help doctors perform surgery procedures more precisely. In clinical surgery, the surgeon often determines the specific surgical location by comparing C-arm X-ray images with digital radiography (DR) images. However, this heavily relies on the doctor's experience. OBJECTIVE: In this study, we design a framework for automatic vertebrae detection as well as vertebral segment matching (VDVM) for the identification of vertebrae in C-arm X-ray images. METHODS: The proposed VDVM framework is mainly divided into two parts: vertebra detection and vertebra matching. In the first part, a data preprocessing method is used to improve the image quality of C-arm X-ray images and DR images. The YOLOv3 model is then used to detect the vertebrae, and the vertebral regions are extracted based on their position. In the second part, the Mobile-Unet model is first used to segment the vertebrae contour of the C-arm X-ray image and DR image based on vertebral regions respectively. The inclination angle of the contour is then calculated using the minimum bounding rectangle and corrected accordingly. Finally, a multi-vertebra strategy is applied to measure the visual information fidelity for the vertebral region, and the vertebrae are matched based on the measured results. RESULTS: We use 382 C-arm X-ray images and 203 full length X-ray images to train the vertebra detection model, and achieve a mAP of 0.87 in the test dataset of 31 C-arm X-ray images and 0.96 in the test dataset of 31 lumbar DR images. Finally, we achieve a vertebral segment matching accuracy of 0.733 on 31 C-arm X-ray images. CONCLUSIONS: A VDVM framework is proposed, which performs well for the detection of vertebrae and achieves good results in vertebral segment matching.


Assuntos
Algoritmos , Coluna Vertebral , Raios X , Coluna Vertebral/diagnóstico por imagem , Radiografia , Fluoroscopia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia
3.
J Xray Sci Technol ; 31(5): 981-999, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37424490

RESUMO

BACKGROUND: Pulmonary granulomatous nodules (GN) with spiculation or lobulation have a similar morphological appearance to solid lung adenocarcinoma (SADC) under computed tomography (CT). However, these two kinds of solid pulmonary nodules (SPN) have different malignancies and are sometimes misdiagnosed. OBJECTIVE: This study aims to predict malignancies of SPNs by a deep learning model automatically. METHODS: A chimeric label with self-supervised learning (CLSSL) is proposed to pre-train a ResNet-based network (CLSSL-ResNet) for distinguishing isolated atypical GN from SADC in CT images. The malignancy, rotation, and morphology labels are integrated into a chimeric label and utilized to pre-train a ResNet50. The pre-trained ResNet50 is then transferred and fine-tuned to predict the malignancy of SPN. Two image datasets of 428 subjects (Dataset1, 307; Dataset2, 121) from different hospitals are collected. Dataset1 is divided into training, validation, and test data by a ratio of 7:1:2 to develop the model. Dataset2 is utilized as an external validation dataset. RESULTS: CLSSL-ResNet achieves an area under the ROC curve (AUC) of 0.944 and an accuracy (ACC) of 91.3%, which was much higher than that of the consensus of two experienced chest radiologists (77.3%). CLSSL-ResNet also outperforms other self-supervised learning models and many counterparts of other backbone networks. In Dataset2, AUC and ACC of CLSSL-ResNet are 0.923 and 89.3%, respectively. Additionally, the ablation experiment result indicates higher efficiency of the chimeric label. CONCLUSION: CLSSL with morphology labels can increase the ability of feature representation by deep networks. As a non-invasive method, CLSSL-ResNet can distinguish GN from SADC via CT images and may support clinical diagnoses after further validation.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Nódulos Pulmonares Múltiplos , Nódulo Pulmonar Solitário , Humanos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Adenocarcinoma de Pulmão/diagnóstico por imagem , Adenocarcinoma de Pulmão/patologia , Tomografia Computadorizada por Raios X/métodos , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Aprendizado de Máquina Supervisionado
4.
Opt Express ; 30(15): 26027-26042, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-36236801

RESUMO

As a coherent diffraction imaging technique, ptychography provides high-spatial resolution beyond Rayleigh's criterion of the focusing optics, but it is also sensitively affected by the decoherence coming from the spatial and temporal variations in the experiment. Here we show that high-speed ptychographic data acquisition with short exposure can effectively reduce the impact from experimental variations. To reach a cumulative dose required for a given resolution, we further demonstrate that a continuous multi-pass scan via high-speed ptychography can achieve high-resolution imaging. This low-dose scan strategy is shown to be more dose-efficient, and has potential for radiation-sensitive sample studies and time-resolved imaging.

5.
PLoS Comput Biol ; 17(8): e1009291, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34437528

RESUMO

Secondary structure plays an important role in determining the function of noncoding RNAs. Hence, identifying RNA secondary structures is of great value to research. Computational prediction is a mainstream approach for predicting RNA secondary structure. Unfortunately, even though new methods have been proposed over the past 40 years, the performance of computational prediction methods has stagnated in the last decade. Recently, with the increasing availability of RNA structure data, new methods based on machine learning (ML) technologies, especially deep learning, have alleviated the issue. In this review, we provide a comprehensive overview of RNA secondary structure prediction methods based on ML technologies and a tabularized summary of the most important methods in this field. The current pending challenges in the field of RNA secondary structure prediction and future trends are also discussed.


Assuntos
Aprendizado de Máquina , Conformação de Ácido Nucleico , RNA/química , Biologia Computacional/métodos
6.
BMC Psychiatry ; 22(1): 588, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-36064380

RESUMO

BACKGROUND: Major depressive disorder (MDD) is a common cause of disability and morbidity, affecting about 10% of the population worldwide. Subclinical depression (SD) can be understood as a precursor of MDD, and therefore provides an MDD risk indicator. The pathogenesis of MDD and SD in humans is still unclear, and the current diagnosis lacks accurate biomarkers and gold standards. METHODS: A total of 40 MDD, 34 SD, and 40 healthy control (HC) participants matched by age, gender, and education were included in this study. Resting-state functional magnetic resonance images (rs-fMRI) were used to analyze the functional connectivity (FC) of the posterior parietal thalamus (PPtha), which includes the lateral habenula, as the region of interest. Analysis of variance with the post hoc t-test test was performed to find significant differences in FC and clarify the variations in FC among the HC, SD, and MDD groups. RESULTS: Increased FC was observed between PPtha and the left inferior temporal gyrus (ITG) for MDD versus SD, and between PPtha and the right ITG for SD versus HC. Conversely, decreased FC was observed between PPtha and the right middle temporal gyrus (MTG) for MDD versus SD and MDD versus HC. The FC between PPtha and the middle frontal gyrus (MFG) in SD was higher than that in MDD and HC. Compared with the HC group, the FC of PPtha-ITG (left and right) increased in both the SD and MDD groups, PPtha-MTG (right) decreased in both the SD and MDD groups and PPtha-MFG (right) increased in the SD group and decreased in the MDD group. CONCLUSION: Through analysis of FC measured by rs-fMRI, the altered FC between PPtha and several brain regions (right and left ITG, right MTG, and right MFG) has been identified in participants with SD and MDD. Different alterations in FC between PPtha and these regions were identified for patients with depression. These findings might provide insights into the potential pathophysiological mechanisms of SD and MDD, especially related to PPtha and the lateral habenula.


Assuntos
Transtorno Depressivo Maior , Habenula , Encéfalo , Mapeamento Encefálico , Depressão , Habenula/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos
7.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 39(6): 1127-1132, 2022 Dec 25.
Artigo em Zh | MEDLINE | ID: mdl-36575081

RESUMO

The radial artery pulse wave contains a wealth of physiological and pathological information about the human body, and non-invasive studies of the radial artery pulse wave can assess arterial vascular elasticity in different age groups.The piezoelectric pulse wave transducers were used to non-invasively acquire radial artery pulse waves at different contact pressures in young and middle-aged and elderly populations. The radial artery waveforms were decomposed using a triangular blood flow model fitting method to obtain forward and reflected waves and calculate reflection parameters. Finally a correlation analysis and regression analysis of the contact pressure Psensor with the reflection parameters was carried out. The results showed that the reflection parameters RM, RI and Rd had a strong negative correlation with Psensor in both types of subjects, and the correlation coefficients and slopes of the regression curves were significantly different between the two types of subjects (P<0.05). Based on the results of this study, excessive contact pressure on the transducer should be avoided when detecting radial artery reflection waves in clinical practice. The results also show that the magnitude of the slope of the regression curve between the reflection parameters and the transducer contact pressure may be a potentially useful indicator for quantifying the elastic properties of the vessel.


Assuntos
Artérias , Análise de Onda de Pulso , Pessoa de Meia-Idade , Idoso , Humanos , Pressão Sanguínea/fisiologia , Velocidade do Fluxo Sanguíneo/fisiologia , Elasticidade , Artéria Radial/fisiologia
8.
J Synchrotron Radiat ; 28(Pt 1): 309-317, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33399582

RESUMO

Ptychography is a rapidly developing scanning microscopy which is able to view the internal structures of samples at a high resolution beyond the illumination size. The achieved spatial resolution is theoretically dose-limited. A broadband source can provide much higher flux compared with a monochromatic source; however, it conflicts with the necessary coherence requirements of this coherent diffraction imaging technique. In this paper, a multi-wavelength reconstruction algorithm has been developed to deal with the broad bandwidth in ptychography. Compared with the latest development of mixed-state reconstruction approach, this multi-wavelength approach is more accurate in the physical model, and also considers the spot size variation as a function of energy due to the chromatic focusing optics. Therefore, this method has been proved in both simulation and experiment to significantly improve the reconstruction when the source bandwidth, illumination size and scan step size increase. It is worth mentioning that the accurate and detailed information of the energy spectrum for the incident beam is not required in advance for the proposed method. Further, we combine multi-wavelength and mixed-state approaches to jointly solve temporal and spatial partial coherence in ptychography so that it can handle various disadvantageous experimental effects. The significant relaxation in coherence requirements by our approaches allows the use of high-flux broadband X-ray sources for high-efficient and high-resolution ptychographic imaging.

9.
J Xray Sci Technol ; 28(5): 821-839, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32773400

RESUMO

BACKGROUND: The novel coronavirus disease 2019 (COVID-19) constitutes a public health emergency globally. The number of infected people and deaths are proliferating every day, which is putting tremendous pressure on our social and healthcare system. Rapid detection of COVID-19 cases is a significant step to fight against this virus as well as release pressure off the healthcare system. OBJECTIVE: One of the critical factors behind the rapid spread of COVID-19 pandemic is a lengthy clinical testing time. The imaging tool, such as Chest X-ray (CXR), can speed up the identification process. Therefore, our objective is to develop an automated CAD system for the detection of COVID-19 samples from healthy and pneumonia cases using CXR images. METHODS: Due to the scarcity of the COVID-19 benchmark dataset, we have employed deep transfer learning techniques, where we examined 15 different pre-trained CNN models to find the most suitable one for this task. RESULTS: A total of 860 images (260 COVID-19 cases, 300 healthy and 300 pneumonia cases) have been employed to investigate the performance of the proposed algorithm, where 70% images of each class are accepted for training, 15% is used for validation, and rest is for testing. It is observed that the VGG19 obtains the highest classification accuracy of 89.3% with an average precision, recall, and F1 score of 0.90, 0.89, 0.90, respectively. CONCLUSION: This study demonstrates the effectiveness of deep transfer learning techniques for the identification of COVID-19 cases using CXR images.


Assuntos
Infecções por Coronavirus/diagnóstico por imagem , Aprendizado Profundo , Pneumonia Viral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Betacoronavirus , COVID-19 , Bases de Dados Factuais , Diagnóstico Diferencial , Humanos , Redes Neurais de Computação , Pandemias , Pneumonia/diagnóstico por imagem , Radiografia Torácica , Reprodutibilidade dos Testes , SARS-CoV-2
10.
Opt Express ; 27(5): 7545-7559, 2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30876317

RESUMO

As the ultrafast laser has been developed, the measurement of ultra-speed transient and dynamic processes has gained much attention. An ultrafast oscilloscope based on the optical stretch method is promising to address this problem, but the measurement is restricted to the temporal profile. This means that the temporal phase is lost. In this work, we propose a full-field ultrafast oscilloscope using two temporal phase retrieval methods: the temporal annealing Gerchberg-Saxton (TAGS) algorithm and temporal ptychography. These could provide complete information, including temporal profile and phase, of high-rate repetitive transient pulses. The functions of an ultrafast oscilloscope with 230 GHz bandwidth and the two phase retrieval methods are verified by simulation and experimental results. This full-field ultrafast oscilloscope promises more applications in phase encoding, phase-contrast imaging, and sensing in the time domain.

11.
Biomed Eng Online ; 18(1): 2, 2019 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-30602393

RESUMO

BACKGROUND: Lung segmentation constitutes a critical procedure for any clinical-decision supporting system aimed to improve the early diagnosis and treatment of lung diseases. Abnormal lungs mainly include lung parenchyma with commonalities on CT images across subjects, diseases and CT scanners, and lung lesions presenting various appearances. Segmentation of lung parenchyma can help locate and analyze the neighboring lesions, but is not well studied in the framework of machine learning. METHODS: We proposed to segment lung parenchyma using a convolutional neural network (CNN) model. To reduce the workload of manually preparing the dataset for training the CNN, one clustering algorithm based method is proposed firstly. Specifically, after splitting CT slices into image patches, the k-means clustering algorithm with two categories is performed twice using the mean and minimum intensity of image patch, respectively. A cross-shaped verification, a volume intersection, a connected component analysis and a patch expansion are followed to generate final dataset. Secondly, we design a CNN architecture consisting of only one convolutional layer with six kernels, followed by one maximum pooling layer and two fully connected layers. Using the generated dataset, a variety of CNN models are trained and optimized, and their performances are evaluated by eightfold cross-validation. A separate validation experiment is further conducted using a dataset of 201 subjects (4.62 billion patches) with lung cancer or chronic obstructive pulmonary disease, scanned by CT or PET/CT. The segmentation results by our method are compared with those yielded by manual segmentation and some available methods. RESULTS: A total of 121,728 patches are generated to train and validate the CNN models. After the parameter optimization, our CNN model achieves an average F-score of 0.9917 and an area of curve up to 0.9991 for classification of lung parenchyma and non-lung-parenchyma. The obtain model can segment the lung parenchyma accurately for 201 subjects with heterogeneous lung diseases and CT scanners. The overlap ratio between the manual segmentation and the one by our method reaches 0.96. CONCLUSIONS: The results demonstrated that the proposed clustering algorithm based method can generate the training dataset for CNN models. The obtained CNN model can segment lung parenchyma with very satisfactory performance and have the potential to locate and analyze lung lesions.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Pulmão/diagnóstico por imagem , Aprendizado de Máquina , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X , Algoritmos , Análise por Conglomerados , Coleta de Dados , Reações Falso-Positivas , Humanos , Redes Neurais de Computação , Curva ROC , Reprodutibilidade dos Testes
12.
Biomed Eng Online ; 18(1): 41, 2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30940144

RESUMO

The physiological processes and mechanisms of an arterial system are complex and subtle. Physics-based models have been proven to be a very useful tool to simulate actual physiological behavior of the arteries. The current physics-based models include high-dimensional models (2D and 3D models) and low-dimensional models (0D, 1D and tube-load models). High-dimensional models can describe the local hemodynamic information of arteries in detail. With regard to an exact model of the whole arterial system, a high-dimensional model is computationally impracticable since the complex geometry, viscosity or elastic properties and complex vectorial output need to be provided. For low-dimensional models, the structure, centerline and viscosity or elastic properties only need to be provided. Therefore, low-dimensional modeling with lower computational costs might be a more applicable approach to represent hemodynamic properties of the entire arterial system and these three types of low-dimensional models have been extensively used in the study of cardiovascular dynamics. In recent decades, application of physics-based models to estimate central aortic pressure has attracted increasing interest. However, to our best knowledge, there has been few review paper about reconstruction of central aortic pressure using these physics-based models. In this paper, three types of low-dimensional physical models (0D, 1D and tube-load models) of systemic arteries are reviewed, the application of three types of models on estimation of central aortic pressure is taken as an example to discuss their advantages and disadvantages, and the proper choice of models for specific researches and applications are advised.


Assuntos
Aorta/fisiologia , Pressão Arterial , Fenômenos Biofísicos , Modelos Biológicos , Humanos
13.
J Xray Sci Technol ; 27(4): 615-629, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31227682

RESUMO

BACKGROUND: Deep learning has made spectacular achievements in analysing natural images, but it faces challenges for medical applications partly due to inadequate images. OBJECTIVE: Aiming to classify malignant and benign pulmonary nodules using CT images, we explore different strategies to utilize the state-of-the-art deep convolutional neural networks (CNN). METHODS: Experiments are conducted using the Lung Image Database Consortium image collection (LIDC-IDRI), which is a public database containing 1018 cases. Three strategies are implemented including to 1) modify some state-of-the-art CNN architectures, 2) integrate different CNNs and 3) adopt transfer learning. Totally, 11 deep CNN models are compared using the same dataset. RESULTS: Study demonstrates that, for the model modification scheme, a concise CifarNet performs better than the other modified CNNs with more complex architectures, achieving an area under ROC curve of AUC = 0.90. Integrated CNN models do not significantly improve the classification performance, but the model complexity is reduced. Transfer learning outperforms the other two schemes and ResNet with fine-tuning leads to the best performance with an AUC = 0.94, as well as the sensitivity of 91% and an overall accuracy of 88%. CONCLUSIONS: Model modification, model integration, and transfer learning can play important roles to identify and generate optimal deep CNN models in classifying pulmonary nodules based on CT images efficiently. Transfer learning is preferred when applying deep learning to medical imaging applications.


Assuntos
Aprendizado Profundo , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Nódulo Pulmonar Solitário/classificação , Bases de Dados Factuais , Humanos , Pulmão/diagnóstico por imagem , Neoplasias Pulmonares/classificação , Neoplasias Pulmonares/diagnóstico por imagem , Curva ROC , Reprodutibilidade dos Testes , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X
14.
Opt Express ; 25(10): 11969-11983, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28788752

RESUMO

The high-frequency vibration of the imaging system degrades the quality of the reconstruction of ptychography by acting as a low-pass filter on ideal diffraction patterns. In this study, we demonstrate that by subtracting the deliberately blurred diffraction patterns from the recorded patterns and adding the properly amplified subtraction to the original data, the high-frequency components lost by the vibration of the setup can be recovered, and thus the image quality can be distinctly improved. Because no prior knowledge regarding the vibrating properties of the imaging system is needed, the proposed method is general and simple and has applications in several research fields.

15.
Quant Imaging Med Surg ; 14(1): 1122-1140, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38223046

RESUMO

Background and Objective: Automatic tumor segmentation is a critical component in clinical diagnosis and treatment. Although single-modal imaging provides useful information, multi-modal imaging provides a more comprehensive understanding of the tumor. Multi-modal tumor segmentation has been an essential topic in medical image processing. With the remarkable performance of deep learning (DL) methods in medical image analysis, multi-modal tumor segmentation based on DL has attracted significant attention. This study aimed to provide an overview of recent DL-based multi-modal tumor segmentation methods. Methods: In in the PubMed and Google Scholar databases, the keywords "multi-modal", "deep learning", and "tumor segmentation" were used to systematically search English articles in the past 5 years. The date range was from 1 January 2018 to 1 June 2023. A total of 78 English articles were reviewed. Key Content and Findings: We introduce public datasets, evaluation methods, and multi-modal data processing. We also summarize common DL network structures, techniques, and multi-modal image fusion methods used in different tumor segmentation tasks. Finally, we conclude this study by presenting perspectives for future research. Conclusions: In multi-modal tumor segmentation tasks, DL technique is a powerful method. With the fusion methods of different modal data, the DL framework can effectively use the characteristics of different modal data to improve the accuracy of tumor segmentation.

16.
IEEE J Biomed Health Inform ; 28(2): 893-904, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38019618

RESUMO

Unsupervised domain adaptation (UDA) methods have shown great potential in cross-modality medical image segmentation tasks, where target domain labels are unavailable. However, the domain shift among different image modalities remains challenging, because the conventional UDA methods are based on convolutional neural networks (CNNs), which tend to focus on the texture of images and cannot establish the global semantic relevance of features due to the locality of CNNs. This paper proposes a novel end-to-end Swin Transformer-based generative adversarial network (ST-GAN) for cross-modality cardiac segmentation. In the generator of ST-GAN, we utilize the local receptive fields of CNNs to capture spatial information and introduce the Swin Transformer to extract global semantic information, which enables the generator to better extract the domain-invariant features in UDA tasks. In addition, we design a multi-scale feature fuser to sufficiently fuse the features acquired at different stages and improve the robustness of the UDA network. We extensively evaluated our method with two cross-modality cardiac segmentation tasks on the MS-CMR 2019 dataset and the M&Ms dataset. The results of two different tasks show the validity of ST-GAN compared with the state-of-the-art cross-modality cardiac image segmentation methods.


Assuntos
Fontes de Energia Elétrica , Coração , Humanos , Redes Neurais de Computação , Semântica , Processamento de Imagem Assistida por Computador
17.
Comput Med Imaging Graph ; 113: 102351, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38335784

RESUMO

Low resolution of positron emission tomography (PET) limits its diagnostic performance. Deep learning has been successfully applied to achieve super-resolution PET. However, commonly used supervised learning methods in this context require many pairs of low- and high-resolution (LR and HR) PET images. Although unsupervised learning utilizes unpaired images, the results are not as good as that obtained with supervised deep learning. In this paper, we propose a quasi-supervised learning method, which is a new type of weakly-supervised learning methods, to recover HR PET images from LR counterparts by leveraging similarity between unpaired LR and HR image patches. Specifically, LR image patches are taken from a patient as inputs, while the most similar HR patches from other patients are found as labels. The similarity between the matched HR and LR patches serves as a prior for network construction. Our proposed method can be implemented by designing a new network or modifying an existing network. As an example in this study, we have modified the cycle-consistent generative adversarial network (CycleGAN) for super-resolution PET. Our numerical and experimental results qualitatively and quantitatively show the merits of our method relative to the state-of-the-art methods. The code is publicly available at https://github.com/PigYang-ops/CycleGAN-QSDL.


Assuntos
Tomografia por Emissão de Pósitrons , Aprendizado de Máquina Supervisionado , Humanos
18.
Data Brief ; 54: 110405, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38698802

RESUMO

Chinese herbal medicine (CHM) is integral to a traditional Chinese medicine (TCM) system. Accurately identifying Chinese herbal medicine is crucial for quality control and prescription compounding verification. However, with many Chinese herbal medicines and some with similar appearances but different therapeutic effects, achieving precise identification is a challenging task. Traditional manual identification methods have certain limitations, including labor-intensive, inefficient. Deep learning techniques for Chinese herbal medicine identification can enhance accuracy, improve efficiency and lower coats. However, few high-quality Chinese herbal medicine datasets are currently available for deep learning applications. To alleviate this problem, this study constructed a dataset (Dataset 1) containing 3,384 images of 20 common Chinese herbal medicine fruits through web crawling. All images are annotated by TCM experts, making them suitable for training and testing Chinese herbal medicine identification methods. Furthermore, this study establishes another dataset (Dataset 2) of 400 images by taking pictures using smartphones to provide materials for the practical efficacy evaluation of Chinese herbal medicine identification methods. The two datasets form a Ningbo Traditional Chinese Medicine Chinese Herb Medicine (NB-TCM-CHM) Dataset. In Dataset 1 and Dataset 2, each type of Chinese medicine herb is stored in a separate folder, with the folder named after its name. The dataset can be used to develop Chinese herbal medicine identification algorithms based on deep learning and evaluate the performance of Chinese herbal medicine identification methods.

19.
Comput Biol Med ; 170: 108074, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38330826

RESUMO

Traditional Chinese medicine (TCM) is an essential part of the Chinese medical system and is recognized by the World Health Organization as an important alternative medicine. As an important part of TCM, TCM diagnosis is a method to understand a patient's illness, analyze its state, and identify syndromes. In the long-term clinical diagnosis practice of TCM, four fundamental and effective diagnostic methods of inspection, auscultation-olfaction, inquiry, and palpation (IAOIP) have been formed. However, the diagnostic information in TCM is diverse, and the diagnostic process depends on doctors' experience, which is subject to a high-level subjectivity. At present, the research on the automated diagnosis of TCM based on machine learning is booming. Machine learning, which includes deep learning, is an essential part of artificial intelligence (AI), which provides new ideas for the objective and AI-related research of TCM. This paper aims to review and summarize the current research status of machine learning in TCM diagnosis. First, we review some key factors for the application of machine learning in TCM diagnosis, including data, data preprocessing, machine learning models, and evaluation metrics. Second, we review and summarize the research and applications of machine learning methods in TCM IAOIP and the synthesis of the four diagnostic methods. Finally, we discuss the challenges and research directions of using machine learning methods for TCM diagnosis.


Assuntos
Inteligência Artificial , Medicina Tradicional Chinesa , Humanos , Medicina Tradicional Chinesa/métodos , Olfato , Aprendizado de Máquina , Palpação
20.
Biomater Sci ; 12(3): 738-747, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38105707

RESUMO

The potential of 3D bioprinting in tissue engineering and regenerative medicine is enormous, but its implementation is hindered by the reliance on high-strength materials, which restricts the use of low-viscosity, biocompatible materials. Therefore, a major challenge for incorporating 3D bioprinting into tissue engineering is to develop a novel bioprinting platform that can reversibly provide high biological activity materials with a structural support. This study presents a room temperature printing system based on GelMA combined with carrageenan to address this challenge. By leveraging the wide temperature stability range and lubricating properties of carrageenan the room temperature stability of GelMA could be enhanced, as well as creating a solid ink to improve the performance of solid GelMA. Additionally, by utilizing the solubility of carrageenan at 37 °C, it becomes possible to prepare a porous GelMA structure while mimicking the unique extracellular matrix properties of osteocytes through residual carrageenan content and amplifying BMSCs' osteogenesis potential to some extent. Overall, this study provides an innovative technical platform for incorporating a low-viscosity ink into 3D bioprinting and resolves the long-standing contradiction between material printing performance and biocompatibility in bioprinting technology.


Assuntos
Bioimpressão , Alicerces Teciduais , Alicerces Teciduais/química , Carragenina , Impressão Tridimensional , Materiais Biocompatíveis/química , Engenharia Tecidual , Hidrogéis/química , Gelatina/química
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