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1.
Artigo em Inglês | MEDLINE | ID: mdl-38648141

RESUMO

Accurate recognition of fetal anatomical structure is a pivotal task in ultrasound (US) image analysis. Sonographers naturally apply anatomical knowledge and clinical expertise to recognizing key anatomical structures in complex US images. However, mainstream object detection approaches usually treat each structure recognition separately, overlooking anatomical correlations between different structures in fetal US planes. In this work, we propose a Fetal Anatomy Reasoning Network (FARN) that incorporates two kinds of relationship forms: a global context semantic block summarized with visual similarity and a local topology relationship block depicting structural pair constraints. Specifically, by designing the Adaptive Relation Graph Reasoning (ARGR) module, anatomical structures are treated as nodes, with two kinds of relationships between nodes modeled as edges. The flexibility of the model is enhanced by constructing the adaptive relationship graph in a data-driven way, enabling adaptation to various data samples without the need for predefined additional constraints. The feature representation is further enhanced by aggregating the outputs of the ARGR module. Comprehensive experimental results demonstrate that FARN achieves promising performance in detecting 37 anatomical structures across key US planes in tertiary obstetric screening. FARN effectively utilizes key relationships to improve detection performance, demonstrates robustness to small-scale, similar, and indistinct structures, and avoids some detection errors that deviate from anatomical norms. Overall, our study serves as a resource for developing efficient and concise approaches to model inter-anatomy relationships.

2.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(3): 261-266, 2024 Mar 15.
Artigo em Chinês | MEDLINE | ID: mdl-38500416

RESUMO

Objective: To explore the early effectiveness of arthroscopic tri-anchor double-pulley suture-bridge in treatment of medium-size supraspinatus tendon tears. Methods: Between December 2020 and January 2023, 40 patients with medium-size supraspinatus tendon tears were treated with arthroscopic tri-anchor double-pulley suture-bridge. There were 18 males and 22 females, with an average age of 62.6 years (mean, 45-73 years). Among them, 17 patients had trauma history. The main clinical symptom was shoulder pain with hug resistance test (+). The interval from symptom onset to operation was 10.7 months on average (range, 3-36 months). Visual analogue scale (VAS) score, University of California Los Angeles (UCLA) score, American Shoulder and Elbow Surgeons (ASES) score, and shoulder range of motion (ROM) of forward flexion, abduction, and external rotation were used to evaluate shoulder function. MRI was performed to assess the structural integrity and tension of reattached tendon. Patient satisfactions were calculated at last follow-up. Results: All incisions healed by first intention, no complications such as incision infection or nerve injury occurred. All patients were followed up 12-37 months (mean, 18.2 months). At 12 months after operation, VAS score, UCLA score, and ASES score significantly improved when compared with the preoperative scores ( P<0.05). At 3 and 12 months after operation, the ROM of external rotation significantly improved when compared with preoperative one ( P<0.05), and further improved at 12 months after operation ( P<0.05). However, the ROMs of abduction and forward flexion did not improve at 3 months after operation when compared with those before operation ( P>0.05), but significantly improved at 12 months after operation ( P<0.05). Twenty-six patients underwent MRI at 3-6 months, of which 23 patients possessed intact structural integrity, good tendon tension, and tendon healing; 3 patients underwent tendon re-tear. The self-rated satisfaction rate was 92.5% at last follow-up. Conclusion: Arthroscopic tri-anchor double-pulley suture-bridge in treatment of medium-size supraspinatus tendon tears can maximize the tendon-bone contact area, obtain satisfied early effectiveness with high satisfaction rate and low incidence of tendon re-tear. However, the function of abduction is limited at 3 months after operation, and patients need to adhere to rehabilitation training to further improve the joint activity.


Assuntos
Lesões do Manguito Rotador , Manguito Rotador , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Manguito Rotador/cirurgia , Artroscopia , Resultado do Tratamento , Técnicas de Sutura , Lesões do Manguito Rotador/cirurgia , Tendões/cirurgia , Suturas , Amplitude de Movimento Articular , Imageamento por Ressonância Magnética
3.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(1): 22-27, 2024 Jan 15.
Artigo em Chinês | MEDLINE | ID: mdl-38225836

RESUMO

Objective: To investigate short-term effectiveness of arthroscopic repair via modified subacromial viewing portal (hereinafter referred to as modified viewing portal) in treatment of LafosseⅠsubscapularis tendon tears. Methods: A clinical data of 52 patients with LafosseⅠsubscapularis tendon tears, who underwent the arthroscopic repair via modified viewing portal between October 2020 and November 2022 and met the selective criteria, was retrospectively analyzed. There were 15 males and 37 females with an average age of 63.4 years (range, 41-76 years). Twelve patients had trauma history and the other 40 patients had no obvious inducement. The main clinical symptom was shoulder pain and the hug resistance tests were positive in all patients. The interval between symptom onset and admission ranged from 3 to 26 months (mean, 7.2 months). The shoulder pain and function were evaluated by visual analogue scale (VAS) score, American Shoulder and Elbow Surgeons (ASES) score, and University of California Los Angeles (UCLA) score before operation and at 12 months after operation. The shoulder range of motion (ROM) of forward flexion, abduction, and external rotation and the internal rotation strength were measured before operation and at 3 and 12 months after operation. MRI was performed at 3-6 months after operation to assess the tendon healing and the structural integrity and tension of reattached tendon. Patient's satisfactions were calculated at last follow-up. Results: All incisions healed by first intention, no complication such as incision infection or nerve injury occurred. All patients were followed up 12-37 months (mean, 18.5 months). The VAS, UCLA, and ASES scores at 12 months after operation significantly improved when compared with those before operation ( P<0.05). The ROMs of abduction and forward flexion and the internal rotation strength at 3 and 12 months significantly improved when compared with those before operation ( P<0.05); and the ROMs at 12 months significantly improved compared to that at 3 months ( P<0.05). However, there was no significant difference ( P>0.05) in the ROM of external rotation at 3 months compared to that before operation; but the ROM at 12 months significantly improved compared to that before operation and at 3 months after operation ( P<0.05). Thirty-one patients underwent MRI at 3-6 months, of which 28 patients possessed intact structural integrity, good tendon tension and tendon healing; 3 patients underwent tendon re-tear. At last follow-up, 41 patients (78.8%) were very satisfied with the effectiveness, 7 were satisfied (13.5%), and 4 were dissatisfied (7.7%). Conclusion: Arthroscopic repair via modified viewing portal for Lafosse Ⅰsubscapularis tendon tears, which can achieve the satisfactory visualization and working space, can obtain good short-term effectiveness with low overall re-tear risk.


Assuntos
Lesões do Manguito Rotador , Articulação do Ombro , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Manguito Rotador/cirurgia , Lesões do Manguito Rotador/cirurgia , Dor de Ombro , Estudos Retrospectivos , Resultado do Tratamento , Artroscopia , Articulação do Ombro/cirurgia , Tendões/cirurgia , Amplitude de Movimento Articular
4.
Heliyon ; 10(2): e24042, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38293485

RESUMO

Osteoarthritis (OA) is an age-related musculoskeletal disease that results in pain and functional disability. Stem cell therapy has been considered as a promising treatment for OA. In this study, the therapeutic action and potential mechanism of synovial mesenchymal stem cells (SMSCs)-derived exosomes (Exos) in OA cartilage damage were investigated. Cartilage cells were stimulated with IL-1ß to establish an in vitro model of OA cartilage damage. Cartilage cell functions were detected by CCK-8, scratch assay, and flow cytometry, respectively. Inflammatory cytokine levels were assessed by ELISA. Target molecule levels were measured by qRT‒PCR and Western blotting. Exos-induced differential expression of miRNAs in cartilage cells were analyzed by microarray analysis. The interaction between miR-485-3p and neuropilin-1 (NRP1) was validated by dual luciferase reporter and RIP assays. We found that treatment with Exos promoted proliferation, migration, and ECM secretion, but restrained apoptosis and inflammation of IL-1ß-exposed cartilage cells via up-regulation of miR-485-3p. Additionally, miR-485-3p directly targeted NRP1 to repress NRP1 expression, which subsequently caused inactivation of the PI3K/Akt pathway. The protective effect of Exos on cartilage damage was counteracted by NRP1 overexpression-mediated activation of the PI3K/Akt pathway. In conclusion, Exos delivered miR-485-3p to attenuate IL-1ß-induced cartilage degradation by targeting NRP1 and succedent inactivation of the PI3K/Akt pathway. Our findings shed light on the novel protective mechanism of Exos in OA, which suggest that the restoration of miR-485-3p by Exos might be a novel approach for OA treatment.

5.
Comput Biol Med ; 169: 107898, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38176210

RESUMO

Accurate segmentation of the thyroid gland in ultrasound images is an essential initial step in distinguishing between benign and malignant nodules, thus facilitating early diagnosis. Most existing deep learning-based methods to segment thyroid nodules are learned from only a single view or two views, which limits the performance of segmenting nodules at different scales in complex ultrasound scanning environments. To address this limitation, this study proposes a multi-view learning model, abbreviated as MLMSeg. First, a deep convolutional neural network is introduced to encode the features of the local view. Second, a multi-channel transformer module is designed to capture long-range dependency correlations of global view between different nodules. Third, there are semantic relationships of structural view between features of different layers. For example, low-level features and high-level features are endowed with hidden relationships in the feature space. To this end, a cross-layer graph convolutional module is proposed to adaptively learn the correlations of high-level and low-level features by constructing graphs across different layers. In addition, in the view fusion, a channel-aware graph attention block is devised to fuse the features from the aforementioned views for accurate segmentation of thyroid nodules. To demonstrate the effectiveness of the proposed method, extensive comparative experiments were conducted with 14 baseline methods. MLMSeg achieved higher Dice coefficients (92.10% and 83.84%) and Intersection over Union scores (86.60% and 73.52%) on two different thyroid datasets. The exceptional segmentation capability of MLMSeg for thyroid nodules can greatly assist in localizing thyroid nodules and facilitating more precise measurements of their transverse and longitudinal diameters, which is of significant clinical relevance for the diagnosis of thyroid nodules.


Assuntos
Nódulo da Glândula Tireoide , Humanos , Ultrassonografia , Redes Neurais de Computação , Semântica , Processamento de Imagem Assistida por Computador
6.
Med Image Anal ; 91: 103039, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37992495

RESUMO

Ultrasound has become the most widely used modality for thyroid nodule diagnosis, due to its portability, real-time feedback, lack of toxicity, and low cost. Recently, the computer-aided diagnosis (CAD) of thyroid nodules has attracted significant attention. However, most existing techniques can only be applied to either static images with prominent features (manually selected from scanning videos) or rely on 'black boxes' that cannot provide interpretable results. In this study, we develop a user-friendly framework for the automated diagnosis of thyroid nodules in ultrasound videos, by simulating the typical diagnostic workflow used by radiologists. This process consists of two orderly part-to-whole tasks. The first interprets the characteristics of each image using prior knowledge, to obtain corresponding frame-wise TI-RADS scores. Associated embedded representations not only provide diagnostic information for radiologists but also reduce computational costs. The second task models temporal contextual information in an embedding vector sequence and selectively enhances important information to distinguish benign and malignant thyroid nodules, thereby improving the efficiency and generalizability of the proposed framework. Experimental results demonstrated this approach outperformed other state-of-the-art video classification methods. In addition to assisting radiologists in understanding model predictions, these CAD results could further ease diagnostic workloads and improve patient care.


Assuntos
Nódulo da Glândula Tireoide , Humanos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/patologia , Sensibilidade e Especificidade , Diagnóstico Diferencial , Ultrassonografia/métodos , Diagnóstico por Computador/métodos
7.
Artigo em Inglês | MEDLINE | ID: mdl-37930929

RESUMO

Biometric parameter measurements are powerful tools for evaluating a fetus's gestational age, growth pattern, and abnormalities in a 2D ultrasound. However, it is still challenging to measure fetal biometric parameters automatically due to the indiscriminate confusing factors, limited foreground-background contrast, variety of fetal anatomy shapes at different gestational ages, and blurry anatomical boundaries in ultrasound images. The performance of a standard CNN architecture is limited for these tasks due to the restricted receptive field. We propose a novel hybrid Transformer framework, TransFSM, to address fetal multi-anatomy segmentation and biometric measurement tasks. Unlike the vanilla Transformer based on a single-scale input, TransFSM has a deformable self-attention mechanism so it can effectively process multi-scale information to segment fetal anatomy with irregular shapes and different sizes. We devised a BAD to capture more intrinsic local details using boundary-wise prior knowledge, which compensates for the defects of the Transformer in extracting local features. In addition, a Transformer auxiliary segment head is designed to improve mask prediction by learning the semantic correspondence of the same pixel categories and feature discriminability among different pixel categories. Extensive experiments were conducted on clinical cases and benchmark datasets for anatomy segmentation and biometric measurement tasks. The experiment results indicate that our method achieves state-of-the-art performance in seven evaluation metrics compared with CNN-based, Transformer-based, and hybrid approaches. By Knowledge distillation, the proposed TransFSM can create a more compact and efficient model with high deploying potential in resource-constrained scenarios. Our study serves as a unified framework for biometric estimation across multiple anatomical regions to monitor fetal growth in clinical practice.

8.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 37(11): 1380-1385, 2023 Nov 15.
Artigo em Chinês | MEDLINE | ID: mdl-37987048

RESUMO

Objective: To investigate the early effectiveness of arthroscopic repair of supraspinatus tendon tears with douple-pulley suture-bridge. Methods: The clinical data of 38 patients with supraspinatus tendon tears who met the selection criteria between September 2020 and July 2022 were retrospectively analyzed, and all of them were treated with arthroscopic double-pulley suture-bridge technique. There were 15 males and 23 females, aged from 43 to 77 years, with an average of 61.5 years. There were 15 cases of left shoulder and 23 cases of right shoulder. Seven cases had a history of trauma, and the other 31 cases had no obvious inducement. The main clinical symptoms of the patient were pain in lifting the shoulder joint and hug resistance test (+). The time from onset of symptoms to admission ranged from 6 to 19 months, with an average of 10.3 months. Flexion, abduction, and external rotation of the shoulder were recorded before operation and at 3 and 12 months after operation. Pain and function of the shoulder were evaluated by visual analogue scale (VAS) score, University of California Los Angeles (UCLA) shoulder score, and American Society of Shoulder and Elbow Surgeons (ASES) score before operation and at 12 months after operation. Tendon healing, tendon continuity, and tension were evaluated by MRI at 3-6 months after operation, and patient's satisfaction was evaluated at last follow-up. Results: All the incisions healed by first intention, and there was no complication such as incision infection or nerve injury. All patients were followed up 12-34 months, with an average of 23.3 months. VAS score, UCLA shoulder score, and ASES score at 12 months after operation were significantly better than those before operation ( P<0.05). The external rotation range of shoulder joint significantly improved at 3 and 12 months after operation ( P<0.05), and it further improved at 12 months after operation when compared with 3 months after operation ( P<0.05). There was no significant difference in the range of flexion and abduction at 3 months after operation when compared with those before operation ( P>0.05), but the range of flexion and abduction at 12 months after operation significantly improved when compared with those before operation and at 3 months after operation ( P<0.05). MRI reexamination was performed in 28 patients at 3-6 months after operation. Among them, 25 patients had intact supraspinatus tendon structure, good tension, and tendon healing, and 3 patients had type 1 retear. The remaining 10 patients refused to undergo MRI reexamination because of the satisfactory effectiveness. At last follow-up, 29 patients (76.3%) were very satisfied with the results, 6 (15.7%) were satisfied, and 3 (7.8%) were not satisfied. Conclusion: Arthroscopic double-pulley suture-bridge technique can achieve the effect of suture bridge operation, reduce the cost of operation and the risk of type 2 retear, and the early effectiveness is satisfactory, but the shoulder joint movement is limited within 3 months after operation.


Assuntos
Lesões do Manguito Rotador , Manguito Rotador , Masculino , Feminino , Humanos , Manguito Rotador/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Artroscopia/métodos , Lesões do Manguito Rotador/cirurgia , Tendões/cirurgia , Suturas , Técnicas de Sutura , Dor/cirurgia , Amplitude de Movimento Articular
9.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 37(6): 653-657, 2023 Jun 15.
Artigo em Chinês | MEDLINE | ID: mdl-37331938

RESUMO

Objective: To explore the mid-term effectiveness of arthroscopic "mini incision" transtendon repair for partial articular-sided supraspinatus tendon avulsion (PASTA) lesion. Methods: A clinical data of 39 patients with PASTA lesions, who underwent the arthroscopic "mini incision" transtendon repair and met the selected criteria between May 2017 and April 2021, was retrospectively analyzed. There were 13 males and 26 females, with an average age of 63.7 years (range, 43-76 years). Nine patients underwent trauma history, and no obvious inducement was found in the other 30 patients. The main clinical symptom was shoulder pain with positive hug resistance test. The interval from symptom onset to operation was 3-21 months (mean, 8.3 months). The visual analogue scale (VAS) score, University of California Los Angeles (UCLA) shoulder score, American Association of Shoulder and Elbow Surgeons (ASES) score and shoulder range of motion (ROM) of forward flexion, abduction, and external rotation were used to evaluate shoulder function. MRI was performed to assess the structural integrity and tension of reattached tendon. Patient satisfactions were calculated at last follow-up. Results: All incisions healed by first intention with no complications such as incision infection or nerve injury. All patients were followed up 24-71 months (mean, 46.9 months). The VAS, UCLA, and ASES scores significantly improved at 24 months after operation when compared with preoperative ones ( P<0.05). The ROMs of forward flexion and external rotation of the shoulder joint significantly increased at 3 and 24 months, and further increased at 24 months compared to 3 months, with significant differences ( P<0.05). However, the ROM of abduction of the shoulder joint at 3 months did not significantly improve compared with that before operation ( P>0.05), and it was significantly greater at 24 months than before operation and at 3 months after operation ( P<0.05). At last follow-up, the patients were very satisfied with the effectiveness in 30 cases (76.9%), satisfied in 5 cases (12.8%), and dissatisfied in 4 cases (10.3%). At 6 months after operation, 31 patients underwent reviews of MRI scans, of which 28 patients possessed intact structural integrity, good tendon tension and tendon healing, and 3 patients underwent tendon re-tear. Conclusion: Arthroscopic "mini incision" transtendon repair in treatment of PASTA lesion could obtain satisfying mid-term effectiveness with low risk of tendon re-tear.


Assuntos
Lesões do Manguito Rotador , Articulação do Ombro , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Manguito Rotador/cirurgia , Lesões do Manguito Rotador/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Artroscopia , Articulação do Ombro/cirurgia , Tendões/cirurgia , Amplitude de Movimento Articular
10.
IEEE J Biomed Health Inform ; 27(10): 5023-5031, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36173776

RESUMO

The ultrasound standard plane plays an important role in prenatal fetal growth parameter measurement and disease diagnosis in prenatal screening. However, obtaining standard planes in a fetal ultrasound video is not only laborious and time-consuming but also depends on the clinical experience of sonographers to a certain extent. To improve the acquisition efficiency and accuracy of the ultrasound standard plane, we propose a novel detection framework that utilizes both the coarse-to-fine detection strategy and multi-task learning mechanism for feature-fused images. First, traditional manually-designed features and deep learning-based features are fused to obtain low-level shared features, which can enhance the model's feature expression ability. Inspired by the process of human recognition, ultrasound standard plane detection is divided into a coarse process of plane type classification and a fine process of standard-or-not detection, which is implemented via an end-to-end multi-task learning network. The region-of-interest area is also recognised in our detection framework to suppress the influence of a variable maternal background. Extensive experiments are conducted on three ultrasound planes of the first-class fetal examination, i.e., the femur, thalamus, and abdomen ultrasound images. The experiment results show that our method outperforms competing methods in terms of accuracy, which demonstrates the efficacy of the proposed method and can reduce the workload of sonographers in prenatal screening.


Assuntos
Diagnóstico Pré-Natal , Ultrassonografia Pré-Natal , Gravidez , Feminino , Humanos , Ultrassonografia Pré-Natal/métodos
11.
Artigo em Inglês | MEDLINE | ID: mdl-37015581

RESUMO

In prenatal examinations, the fetal head circumference (HC) measurement is essential for assessing fetal weight and health conditions. The sonographers obtain the fetal HC manually by fitting peripheral skull ellipse in clinical practice, which is highly subjective, time-consuming, and experience-dependent. Recently, many fetal HC automatic measurement algorithms have been proposed to improve workflow efficiency in prenatal examination. But most automatic measurement algorithms focus on using fetal head segmentation as an intermediate processing step, and HC estimation relies heavily on segmentation results, which causes the accumulation of errors in the above two stages. Independent of the segmentation method, we design a regression network to generate the oriented bounding box to detect the head contour, and directly obtain the fetal head parameters with a pixel-based ellipse regression (PER) loss. Moreover, an effective 3D attention mechanism is integrated into the network to estimate HC more precisely without adding parameters in complex ultrasound images. The extensive experimental results on the public HC18 and our clinical dataset show that the proposed network provides a feasible scheme for end-to-end estimating fetal HC, and avoids the mistake brought by the intermediary processes.

12.
Med Phys ; 49(1): 382-392, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34730231

RESUMO

BACKGROUND: The prevalence of thyroid diseases has been increasing year by year. In this study, we established and validated a deep learning method (Cascade region-based convolutional neural network, R-CNN) based on ultrasound videos for automatic detection and segmentation of the thyroid gland and its surrounding tissues in order to reduce the workload of radiologists and improve the detection and diagnosis rate of thyroid disease. METHODS: Seventy-one patients with normal thyroid ultrasound were included. The ultrasound videos of 59 patients were used as the training dataset, the data of 12 patients were used as the validation dataset, and in addition, the data of 9 patents were used as the testing dataset. Ultrasound videos of thyroid examination, including five standard sections (left and right lobe transverse scan, central isthmus transverse scan, left and right lobe longitudinal scan), were collected from all patients. The radiologists labeled the neck tissues, including anterior cervical muscle, cricoid cartilage, trachea, thyroid gland, endothyroid vessels, carotid artery, internal jugular vein, and esophagus. A large dataset was constructed to train and test the deep learning method. The performance was evaluated using the COCO metrics AP, AP50, and AP75. We compared the Cascade R-CNN with a state-of-the-art method CenterMask in the test dataset. RESULTS: We annotated 166817, 34364, and 29227 regions in training, validation and testing samples. The model could achieve a good detection performance for the thyroid left lobe, right lobe, isthmus, muscles, trachea, carotid artery, and jugular vein; the AP50 of these tissues were 86.5%, 87.5%, 89.1%, 96.1%, 96.6%, 97.7%, and 91.8%, respectively. In addition, the model showed good segmentation performance for the muscles, trachea, and carotid artery; the AP50 of these tissues were 96%, 96.6%, and 97.8%, respectively. For the left lobe, right lobe, isthmus, esophagus, and jugular vein, AP50 was ≥86%. However, the segmentation results for the cricoid cartilage and endothyroid vessels were not high (AP50 of 53.9% and 48.5%, respectively). For fair comparison, the performance of Cascade R-CNN is better than that of CenterMask for detection and segmentation tasks. The difference was statistically significant (p < 0.05). CONCLUSIONS: The new method could successfully detect and segment the thyroid gland and its surrounding tissues.


Assuntos
Aprendizado Profundo , Glândula Tireoide , Humanos , Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Glândula Tireoide/diagnóstico por imagem , Ultrassom , Ultrassonografia
13.
Langmuir ; 37(43): 12616-12628, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34672608

RESUMO

Development of high-efficiency oxygen reduction reaction (ORR) catalysts under neutral conditions has made little research progress. In this work, we synthesized a three-dimensional porous N/P codoped carbon nanosheet composites (CNP@PNS) by high-temperature thermal treatment of dicyandiamide, starch, and triphenylphosphine and subsequent porous structure-making treatment using the NaCl molten salt template. In the neutral solution, the electrocatalytic performance of the CNP@PNS-4 catalyst exhibits an onset potential of 0.98 V (vs reversible hydrogen electrode) and a half-wave potential of 0.91 V for ORR, which greatly surpasses commercial Pt/C (40%). Three kinds of neutral metal-air batteries (Zn-air, Al-air, and Fe-air) using the prepared samples as cathodic catalysts were constructed, corresponding to the maximum power density of 120.2, 78.3, and 18.9 mW·cm-2, respectively. Also, they reveal outstanding discharge stability under different current densities. The density functional theory calculation depicts the reduction of the free energy of the determining step and subsequent decline of the overpotential for ORR.

14.
IEEE J Biomed Health Inform ; 25(10): 3812-3823, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34057900

RESUMO

To accurately detect and track the thyroid nodules in a video is a crucial step in the thyroid screening for identification of benign and malignant nodules in computer-aided diagnosis (CAD) systems. Most existing methods just perform excellent on static frames selected manually from ultrasound videos. However, manual acquisition is labor-intensive work. To make the thyroid screening process in a more natural way with less labor operations, we develop a well-designed framework suitable for practical applications for thyroid nodule detection in ultrasound videos. Particularly, in order to make full use of the characteristics of thyroid videos, we propose a novel post-processing approach, called Cache-Track, which exploits the contextual relation among video frames to propagate the detection results into adjacent frames to refine the detection results. Additionally, our method can not only detect and count thyroid nodules, but also track and monitor surrounding tissues, which can greatly reduce the labor work and achieve computer-aided diagnosis. Experimental results show that our method performs better in balancing accuracy and speed.


Assuntos
Nódulo da Glândula Tireoide , Diagnóstico por Computador , Humanos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Ultrassonografia
15.
Quant Imaging Med Surg ; 10(9): 1775-1785, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32879856

RESUMO

BACKGROUND: Existing studies have demonstrated that imaging parameters may affect radiomic features. However, the influence of feature calculating parameters has been overlooked. The purpose of this study is to investigate the influence of feature calculating parameters (gray-level range and bin size) on the reproducibility of CT radiomic features. METHODS: Thirty-six CT scans from an anthropomorphic thoracic phantom were acquired with different imaging parameters including effective dose, pitch, slice thicknesses and reconstruction kernels. The influence of feature calculating parameters was investigated in terms of three gray-level ranges and eleven gray-level bin sizes. Feature reproducibility was assessed by the intraclass correlation coefficient (ICC) with the cutoff value of 0.8 and the coefficient of variation (CV) with the cutoff value of 20%. The agreements of reproducible features in different ranges and bin sizes were analyzed by Kendall's W test and Kappa test. The proportions of reproducible features, in terms of two calculating, four imaging and two segmentation parameters, were evaluated using Cochran's Q test and Dunn's test. RESULTS: For the three gray-level ranges, 50% (44/88) of features were reproducible with a perfect agreement (Kendall's W coefficient 0.844, P<0.001). Of the 72 features that may be influenced by gray-level bin size, 33.3% (24/72) were reproducible for 11 bin sizes with a perfect agreement (Kendall's W coefficient 0.879, P<0.001). For the proportions of reproducible features, there was no statistically significant difference among three ranges (P=0.420), but there was among eleven bin sizes (P=0.013). The proportions of reproducible features in feature calculating parameters were statistically significantly lower than those in imaging parameters (adjusted P<0.05). CONCLUSIONS: Feature calculating parameters may have a greater influence than imaging parameters on the reproducibility of CT radiomic features, which should be given special attention in clinical applications.

16.
Tumour Biol ; 2017 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-28050866

RESUMO

MicroRNAs (miRNAs) are a type of small noncoding RNAs that often play important roles in carcinogenesis, but the carcinogenic mechanism of miRNAs is still unclear. This study will investigate the functions and the mechanism of miR-638 in osteosarcoma (OS). The expression of miR-638 in OS and the DNA copy number of miR-638 were detected by real-time PCR. The effect of miR-638 on cell proliferation was measured by CCK8 assay. Different assays, including bioinformatics algorithms, luciferase report assay, and Western blotting, were used to identify the target gene proviral integration site for Moloney murine leukemia virus 1 (PIM1) of miR-638 in OS. The expression of PIM1 in clinical OS tissues was also validated by immunohistochemical assay. From this research, we found that miR-638 was downregulated in OS tissues compared with corresponding noncancerous tissues (NCTs), and the DNA copy number of miR-638 was lower in OS than in NCTs, which may induce the corresponding downregulation of miR-638 in OS. Ectopic expression of miR-638 inhibited OS cell growth in vitro. Subsequently, we identified that PIM1 is the downstream target gene of miR-638 in OS cells, and silencing PIM1 expression phenocopied the inhibitory effect of miR-638 on OS cell proliferation. Furthermore, we observed that PIM1 was overexpressed in OS tissues, and high expression of PIM1 in OS predicted poor overall survival. In summary, we revealed that miR-638 functions as a tumor suppressor through inhibiting PIM1 expression in OS.

17.
Tumour Biol ; 37(11): 14923-14928, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27644251

RESUMO

It is stated that high expression of pyruvate kinase (PKM2) emerges as a significant player in the metabolism and progression of various human malignancies. However, the expression of PKM2 and its association with the prognosis of osteosarcoma had not yet been studied. In the present study, the expression and biological significance of PKM2 in osteosarcoma were investigated. We found that PKM2 expression was elevated in the cancerous tissues and it was more abundant than the adjacent normal tissues (60.2 vs 26.1 %, p < 0.001). Moreover, we showed that high PKM2 expression was positively correlated with Enneking stage (p = 0.006) and distant metastasis (p = 0.007) but not with the age, gender, tumor site, tumor size, histologic grade, alkaline phosphatase (ALP), lactate dehydrogenase (LDH), and local pain of the patients. Furthermore, Kaplan-Meier analysis revealed that the overall survival (OS) for patients with high PKM2 expression was significantly lower than those with low PKM2 expression (p < 0.001). Finally, multivariate analysis revealed that high PKM2 expression was an independent prognostic factor for osteosarcoma patients (p = 0.004). Collectively, these data indicated that elevated PKM2 might serve as a novel target for the treatment of osteosarcoma.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Ósseas/patologia , Proteínas de Transporte/metabolismo , Proteínas de Membrana/metabolismo , Osteossarcoma/patologia , Piruvato Quinase/metabolismo , Hormônios Tireóideos/metabolismo , Adolescente , Neoplasias Ósseas/mortalidade , Progressão da Doença , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Osteossarcoma/mortalidade , Prognóstico , Análise Serial de Tecidos , Proteínas de Ligação a Hormônio da Tireoide
18.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 30(10): 1233-1237, 2016 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-29786202

RESUMO

OBJECTIVE: To detect the expression of human transforming growth factor ß1 (hTGF-ß1) gene mediated by adenovirus (Ad) in hamstring tendon after anterior cruciate ligament (ACL) reconstruction in rabbits. METHODS: Ad-hTGF-ß1 and Ad-green fluorescent protein (GFP) were diluted to 5×108 PFU/mL with DMEM. Forty-eight New Zealand white rabbits were divided into 3 groups randomly (n=16) for ACL reconstruction with hamstring tendon autograft. Hamstring tendon was cultured and transfected with Ad-hTGF-ß1 (group A) and Ad-GFP (group B) for 12 hours before ACL reconstruction, and was cultured with DMEM in group C. After 12 hours of transfection, green fluorescence was observed in groups A and B under fluorescence microscopy. At 2, 4, 6, and 8 weeks after operation, the hamstring tendon was harvested to detect the mRNA and protein expressions of hTGF-ß1 by real time fluorescence quantitative PCR and Western blot. RESULTS: Green fluorescence was observed after 12 hours of transfection in groups A and B. TGF-ß1 protein level reached (221.0±12.2) ng/mL at 12 hours in group A. The hTGF-ß1 mRNA expression could be detected in group A, but it could not be detected in group B and group C. The mRNA expression levels of hTGF-ß1 were 1.004±0.072 at 2 weeks, 0.785±0.038 at 4 weeks, 0.469±0.053 at 6 weeks, and 0.172±0.021 at 8 weeks in group A, showing significant difference (P<0.05). Western blot results showed weakly positive band in groups B and C; the protein expression of TGF-ß1 in group A was significantly higher than that in groups B and C (P<0.05), but no significant difference was found between groups B and C P>0.05). The protein expression of TGF-ß1 gradually reduced with time, showing significant difference between different time points (P<0.05). CONCLUSIONS: Ad-hTGF-ß1 can transfect the hamstring tendon successfully, and it can effectively express for a long time after ACL reconstruction.

19.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 29(12): 1488-93, 2015 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-27044216

RESUMO

OBJECTIVE: To investigate the effect of hamstring tendon transfected with adenovirus-mediated transforming growth factor ß1 (AdTGF-ß1) genes on the histomorphology of tendon-bone interface healing after anterior cruciate ligament (ACL) reconstruction in rabbits. METHODS: AdTGF-ß1 and AdGFP were diluted to 5 x 108 PFU/mL with DMEM. Forty-eight New Zealand white rabbits were divided into 3 groups randomly (n=16), weighing 1.6-2.5 kg for ACL reconstruction with hamstring tendon autograft. Hamstring tendon was cultured and transfected with AdTGF-ß1 (group A) and AdGFP (group B) for 12 hours before ACL reconstruction, and was cultured with DMEM in group C. After 12 hours of transfection, the expression of green fluorescence was observed in groups A and B under fluorescence microscopy; TGF-ß1 protein level was detected by ELISA in group A. At 2, 4, 8, and 12 weeks after operation, the specimens were harvested for HE and Masson staining; the number of fibroblasts was counted, and the Buark grading was used to evaluate tendon-bone interface healing. RESULTS: Green fluorescence was observed after 12 hours of transfection in groups A and B. TGF-ß1 protein level reached (221.0 ± 12.2) ng/mL at 12 hours in group A. The histological observation showed that few fibroblasts and collagen fibers were found, and Sharpey fibers appeared in group A; regular Sharpey fibers were seen in the interface, and integrity interface in some areas at 12 weeks. But fibroblasts of groups B and C were less than those of group A, with loose tendon-bone interface; no integrity interface was observed at 12 weeks. The number of fibroblasts and Buark grading of group A were significantly higher than those of groups B and C (P < 0.05), but no significant difference was found between groups B and C (P > 0.05). CONCLUSION: Hamstring tendon transfected with AdTGF-ß1 gene can promote the healing of tendon-bone interface after ACL reconstruction.


Assuntos
Adenoviridae/genética , Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior/métodos , Transplante Ósseo , Transfecção , Cicatrização , Animais , Osso e Ossos/patologia , Coelhos , Tendões/patologia , Tendões/transplante , Fator de Crescimento Transformador beta1/metabolismo , Transplante Autólogo
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