ABSTRACT
Objective: To compare the sensitivity and specificity between low dose dobutamine stress speckling tracking echocardiography (LDDS-STE) and delayed enhancement MRI (DE-MRI) for assessing viable myocardium (VM) in patients with old myocardial infarction (OMI). Methods: A total of 30 in-hospitalized OMI patients were enrolled, all patients received cardiac MRI and LDDS-STE prior percutaneous coronary intervention (PCI). Radial peak systolic strain (RS) and strain rate (RSr) were analyzed by LDDS-STE at both resting and loading conditions, echocardiography was performed at 1, 3 and 6 months after PCI to observe the cardiac wall motion changes and the improvement of wall motion score was taken as golden standard of VM. Results: 510 left ventricular segments were obtained for analysis in 30 patients and echocardiography indicated 201 segments with abnormal wall motion. Compared with golden standard, the area under ROC curve of RSrest for detecting VM was 0.636 with the sensitivity at 60.0% , specificity at 60.5% and the area under ROC curve of RSLDDS for detecting VM was 0.806 with the sensitivity at 79.1%, specificity at 82.7%; the area under ROC curve of RSrrest for detecting VM was 0.646 with the sensitivity at 60.0% , specificity at 60.5% and the area under ROC curve of RSrLDDS for detecting VM was 0.808 with the sensitivity at 80.0%, specificity at 83.7% which were obviously improved than RSrrest . By DE-MRI, the area under ROC curve for detecting VM was 0.901 with the sensitivity at 90.8%, specificity at 87.1% and accuracy at 89.5%. Conclusion: Both DE-MRI and LDDS-STE can recognize VM in OMI patients; while DE-MRI had the better accuracy and repeatability, cost less time which may provide important basis for predicting the efficacy of PCI and for making the treatment strategy.
ABSTRACT
Purpose To summarize the histological,immunophenotypic feature and MYCN (MYC gene) amplification results of peripheral neuroblastic tumours in children,and to predict its biological behavior and prognosis.Methods The histology and immunophenotype of 100 cases of neuroblastoma (NB) and ganglioneuroblastoma (GNB) were retrospectively analysed,MYCN status was detected in 60 cases.Results Among The average age of 100 cases of GN and GNB was 2.7 years old,and that of males was more than that of females.NB could be divided into three subtypes:undifferentiated,poorly differentiated and differentiating.GNB could be divided into two subtypes:intermixed (iGNB) and nodular (nGNB).Immunohistochemical staining showed neuroblastoma cells were positive for NSE,NF,PGP9.5,Syn,CgA in varying degree.Schwann cells were positive for S-100 and GFAP.MYCN amplification was detected in 1 1.67％ of the cases,and no MYCN amplification was seen in iGNB patients.Conclusion The diagnosis of peripheral neuroblastic tumours is mainly based on histological morphology,special tests (immunohistochemistry,electron microscope and cytogenetics) can helpful for identifing undifferentiated neuroblastoma cells.The prognosis of neuroblastoma derived tumors is evaluated according to the age of patients,the classification and staging of tumors,and molecular genetic alterations.
ABSTRACT
Cells in the body are exposed to physiological and pathophysiological stimuli that encompass both chemical and mechanical factors. It is important to understand how these factors modulate functions at cellular and organ levels. Compared to the large amount of information on cellular or organ responses to chemical factors, there is a paucity of knowledge on the effects of mechanical factors. Recent advances of fluorescence proteins and microscopy make it a very useful tool for elucidating the mechanotransduction processes; the state-of-the-art technologies for live-cell imaging of signaling is particularly valuable for investigating the spatial and temporal aspects of molecular mechanisms in mechanobiology. This review will cover the basic knowledge of fluorescence proteins and their application for biological research. In particular, the development and characterization of biosensors based on fluorescent resonance energy transfer (FRET) will be discussed. Genetically encoded FRET biosensors, which allows the imaging and quantification of tempo-spatial activation of molecules, will be introduced to demonstrate how the initiation and transmission of biochemical signals in response to local mechanical stimulation can be visualized in live cells. Specific emphasis will be on the elucidation of molecule hierarchy of signaling transduction in live cells upon the mechanical stimulation.