ObjectiveTo detect the metabolites of the serum and joint fluid from rabbits’ osteoarthritis model with 1H nuclear magnetic resonance spectroscopy (NMR) technique, study the metabolic differences and connections of serum, synovial and cartilage of rabbits after the articular cavity injection of sodium hyaluronate, and explore osteoarthritis and metabolic mechanism in the process of treating sodium hyaluronate using sodium hyaluronate, thus provide new ideas and basis of the specific mechanisms in the treatment of osteoarthritis via sodium hyaluronate.MethodsWe selected 30 healthy New Zealand white rabbits, 6 months old, and randomly divided them into three groups as follows: blank control group, model phosphate buffer saline (PBS) liquid injection group and model injection of sodium hyaluronate group, with 10 rabbits in each group. Ten weeks after surgery, all experimental animals were put to death and observed in correlation studies regarding general condition, imaging examination, and histological examination. Metabolites 1H NMR detection and data preprocessing were performed in the serum and joint fluid samples.ResultsThe results considering general condition, general sample observation, imaging examination and histology indicated advantages in sodium hyaluronate group over PBS group. Metabolomics analysis showed statistically significant changes of metabolites in the serum and joint fluid compared with the PBS group and the blank control group (P<0.05). According to the relevant ways of differences metabolites retrieval, analysis found that the effect of sodium hyaluronate on osteoarthritis might be related to protein biosynthesis, amino acid circulation, the metabolic process of pyruvic acid, gluconeogenesis and other metabolic pathways.ConclusionsBased on the research of 1H-NMR metabolomics, the results suggest that the effect of sodium hyaluronate on osteoarthritis is mainly related with the activation of protein metabolism, abnormal lipid and energy metabolic pathways. This study provides new ideas and basis on the concrete mechanism in the treatment of knee osteoarthritis using sodium hyaluronate.
ObjectiveTo make the model of Wistar suckling rats Focal cortical dysplasia (FCD) by liquid nitrogen freezing brain cortex and verify it. Analysed the electroencephalogram (EEG) and magnetic resonance imaging (MRI) features of the FCD model, in order to provide theoretical and experimental basis for human FCD diagnosis and treatment. MethodsTake the first day of Wistar suckling rats as experimental object, liquid nitrogen freezing Wistar suckling rats brain cortex.Make examination of EEG and MRI for Wistar suckling rats. The Brain tissue slice of Wistar suckling rats model dyed by HE and check with light microscope examination. ResultsIn experiment group, the sample epileptic discharge rate of EEG was about 41.6% on average, and showed visible spike wave, spine slow wave frequency distribution. Experimental Wistar suckling rats MRI showed positive performance for long T1 and long T2 signal, brain tissue slices HE staining showed brain cortex layer structure and columnar structure disorder, exist abnormal neurons and the balloon sample cells. ConclusionThe method of liquid nitrogen freezing Wistar suckling rats cortex can established FCDⅢd animal models successfully, and showed specific EEG and MRI, which has important value for diagnosis and treatment of human FCD.
OBJECTIVE:To investigate the diagnostic meaning of MRI in intraocular tumors. METHODS:Forty-six cases of confirmed intraocular tumors,including choroidal melanoma(20 cases),retinoblastoma(18 cases),Coats disease(6 cases)and choroidal hemangioma(2 cases),were studied with MRI and compared with ultrasonography and CT. RESULTS:In making discoveries about intraocular tumors,there were no sighificant difference between MRI and B-ultrasonography or CT （P＞0.03，chi;2=1.0716）while there were highly statistic sighificance in dediding characters and position （P＜0.01，deceding character chi;2=29.8314，positionchi;2=13.659）of them. CONCLUSION:Among the examinations to find out about the position,character and secondary pathological insults of in traocular tumors MRI might be more available than CT and ultrasonography. （Chin J Ocul Fundus Dis,1997,13:93-95 ）
多发性硬化临床表现多样,其中大脑半球型多表现为精神症状、癫痫、偏瘫或感觉异常等,而以截瘫及排尿障碍为表现者少见。本文对表现为“脑性截瘫”的3 例MS患者的临床和MRI特点进行回顾分析,以此提高对于MS的认识水平。
When applying deep learning algorithms to magnetic resonance (MR) image segmentation, a large number of annotated images are required as data support. However, the specificity of MR images makes it difficult and costly to acquire large amounts of annotated image data. To reduce the dependence of MR image segmentation on a large amount of annotated data, this paper proposes a meta-learning U-shaped network (Meta-UNet) for few-shot MR image segmentation. Meta-UNet can use a small amount of annotated image data to complete the task of MR image segmentation and obtain good segmentation results. Meta-UNet improves U-Net by introducing dilated convolution, which can increase the receptive field of the model to improve the sensitivity to targets of different scales. We introduce the attention mechanism to improve the adaptability of the model to different scales. We introduce the meta-learning mechanism, and employ a composite loss function for well-supervised and effective bootstrapping of model training. We use the proposed Meta-UNet model to train on different segmentation tasks, and then use the trained model to evaluate on a new segmentation task, where the Meta-UNet model achieves high-precision segmentation of target images. Meta-UNet has a certain improvement in mean Dice similarity coefficient (DSC) compared with voxel morph network (VoxelMorph), data augmentation using learned transformations (DataAug) and label transfer network (LT-Net). Experiments show that the proposed method can effectively perform MR image segmentation using a small number of samples. It provides a reliable aid for clinical diagnosis and treatment.
Coronary microcirculation dysfunction (CMVD) is an important risk factor for the prognosis of re-perfused ischemic heart. Recent studies showed that the evaluation of CMVD has significant impact on both the early diagnosis of heart diseases relevant to blood supply and prognosis after myocardial reperfusion. In this review, the definition of CMVD from the perspective of pathophysiology was clarified, the principles and features of the state-of-the-art imaging technologies for CMVD assessment were reviewed from the perspective of engineering and the further research direction was promoted.
In order to solve the pathological grading of hepatocellular carcinomas (HCC) which depends on biopsy or surgical pathology invasively, a quantitative analysis method based on radiomics signature was proposed for pathological grading of HCC in non-contrast magnetic resonance imaging (MRI) images. The MRI images were integrated to predict clinical outcomes using 328 radiomics features, quantifying tumour image intensity, shape and text, which are extracted from lesion by manual segmentation. Least absolute shrinkage and selection operator (LASSO) were used to select the most-predictive radiomics features for the pathological grading. A radiomics signature, a clinical model, and a combined model were built. The association between the radiomics signature and HCC grading was explored. This quantitative analysis method was validated in 170 consecutive patients (training dataset: n = 125; validation dataset, n = 45), and cross-validation with receiver operating characteristic (ROC) analysis was performed and the area under the ROC curve (AUC) was employed as the prediction metric. Through the proposed method, AUC was 0.909 in training dataset and 0.800 in validation dataset, respectively. Overall, the prediction performances by radiomics features showed statistically significant correlations with pathological grading. The results showed that radiomics signature was developed to be a significant predictor for HCC pathological grading, which may serve as a noninvasive complementary tool for clinical doctors in determining the prognosis and therapeutic strategy for HCC.
Urokinase plasminogen activator receptor (uPAR) is a membrane protein which is attached to the cellular external membrane. The uPAR expression can be observed both in tumor cells and in tumor-associated stromal cells. Thus, in the present study, the human amino-terminal fragment (hATF), as a targeting element to uPAR, is used to conjugate to the surface of superparamagnetic iron nanoparticle (SPIO). Flowcytometry was used to examine the uPAR expression in different tumor cell lines. The specificity of hATF-SPIO was verified by Prussian blue stain and cell phantom test. The imaging properties of hATF-SPIO were confirmed in vivo magnetic resonance imaging (MRI) of uPAR-elevated colon tumor. Finally, the distribution of hATF-SPIO in tumor tissue was confirmed by pathological staining. Results showed that the three cells in which we screened, presented different expression characteristics, i.e., Hela cells strongly expressed uPAR, HT29 cells moderately expressed uPAR, but Lovo cells didn't express uPAR. In vitro, after incubating with Hela cells, hATF-SPIO could specifically combined to and be subsequently internalized by uPAR positive cells, which could be observed via Prussian blue staining. Meanwhile T2WI signal intensity of Hela cells, after incubation with targeted probe, significantly decreased, and otherwise no obvious changes in Lovo cells both by Prussian blue staining and MRI scans. In vivo, hATF-SPIO could be systematically delivered to HT29 xenograft and accumulated in the tumor tissue which was confirmed by Prussian Blue stain compared to Lovo xenografts. Twenty-four hours after injection of targeting probe, the signal intensity of HT29 xenografts was lower than Lovo ones which was statistically significant. This targeting nanoparticles enabled not only in vitro specifically combining to uPAR positive cells but also in vivo imaging of uPAR moderately elevated colon cancer lesions.