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2017 Vol. 36, No. 3 Published: 2017-06-20 Reviews Communications Regular Papers        Regular Papers 257 Bone Joints Localization in Mouse Micro-CT Images Using Random Forests Algorithm Tu Ruibo, Chen Zhonghua, Wang Hongkai DOI: 10.3969/j.issn.0258-8021.2017.03.001 Along with the rapid development of imaging techniques for small animals, more and more images obtained from small animals need to be analyzed per day, therefore automated image analysis method has become an urgent demand. For mice images, the significant inter-subject posture variations become a major difficulty for automated image analysis. In this paper, an automatic bone joint localization method was developed for mouse micro-CT images, so as to help with posture identification of mouse body. The proposed method was composed of three steps: (1) classification random forests for rough joint localization, (2) aggregating the results of classification through regression forest, and (3) picking up landmarks in the right position by the mapping graph. The method achieved automatic bone joint localization for 49 test images of different body postures. The median localization error of the whole body CT images was 0.68 mm. The success rate of localization was 98.27%. We also demonstrated the necessity of combining classification and regression random forest and discussed the influence on localization with different number of training data. With this new method for mouse micro-CT posture identification was expected to provide helpful information for the subsequent image registration, segmentation and measurements. 2017 Vol. 36 (3): 257-266 [Abstract] ( 474 ) HTML (1 KB)  PDF (3618 KB)  ( 699 ) 267 Fetal Facial Standard Plane Recognition via Deep Convolutional Neural Networks Yu Zhen, Wu Lingyun, Ni Dong, Chen Siping, Li Shengli, Wang Tianfu, Lei Baiying DOI: 10.3969/j.issn.0258-8021.2017.03.002 The accurate recognition of fetal facial standard plane (FFSP) (i.e., axial, coronal and sagittal plane) from ultrasound (US) images is quite essential for routine US examination. Since the labor-intensive and subjective measurement is too time-consuming and unreliable, the development of the automatic FFSP recognition method is highly desirable. In this paper, we proposed to recognize FFSP using different depth CNN architectures (e.g., 8-layer and 16-layer). Specifically, we trained these models varied from depth to depth and mainly utilize two training strategy: 1) training the “CNN from scratch” with random initialization; 2) performing transfer learning strategy by fine-tuning ImageNet pre-trained CNN on our FFSP dataset. In our experiments, fetal gestational ages ranged typically from 20 to 36 weeks. Our training dataset contains 4849 images (i.e., 375 axial plane images, 257 coronal plane images, 405 sagittal plane images and 3812 non-FFSP images). Our testing dataset contained 2 418 images (i.e., 491 axial plane images, 127 coronal plane images, 174 sagittal plane images, and 1626 non-FFSP images). The experiment indicated that the strategy of transfer learning combined with CNN improving recognition accuracy by 9.29%. When CNN depth changes from 8 layer to 16 layer, it improves the recognition accuracy by 3.17%. The best recognition accuracy of our CNN model was 94.5%, which was 3.66% higher than our previous study. The effectiveness of deep CNN and transfer learning for FFSP recognition shows promising application for clinical diagnosis. 2017 Vol. 36 (3): 267-275 [Abstract] ( 508 ) HTML (1 KB)  PDF (7909 KB)  ( 540 ) 276 A Deep Convolutional Networks and Combination Strategy for Automated Nuclear Atypia Grading on Breast Histopathology Zhou Chao, Xu Jun, Luo Bo DOI: 10.3969/j.issn.0258-8021.2017.03.003 Nuclear atypia is one of important factors in Nottingham Grading System (NGS) for evaluating the aggressiveness of breast cancer. The nuclear atypia is mainly manifested in change of the nuclear shape, size, texture and uneven density. However, histologic image has complicated nature that makes the automated nuclei atypia grading a pretty difficult task. In the paper we integrated deep convolutional neural networks and combination strategy for automated nuclei atypia grading. Firstly, the histologic patches with three different resolutions were cropped into same size for training three convolutional neural networks models, respectively. During the testing, a sliding window technique was employed to choose image patches and feed to the trained DCNN. Then the majority voting was used to evaluate the grade of the image under each resolution. Finally, plurality voting was employed to evaluate the score based on three different resolutions. The proposed model got 67 points in the test set, ranking the 2nd comparing with all of current methods with good performance. Moreover, the proposed approach was computationally efficient. The average computational time on each images with the resolution of ×10, ×20, ×40 were 1.2, 5.5, and 30 seconds, respectively, indicating that the proposed approach can be applied in clinical routine procedure for automated grading of nuclei atypia on histologic images. 2017 Vol. 36 (3): 276-283 [Abstract] ( 426 ) HTML (1 KB)  PDF (4691 KB)  ( 1660 ) 284 Assessment of the Coupling Between Heart Rate and Arterial Pressure During Head-Up Tilt Zhan Ping, Li Chenxi, Wang Zhigang, Zhang Zhengguo, Peng Yi DOI: 10.3969/j.issn.0258-8021.2017.03.004 This study is aimed to investigate the changes of the coupling strength between RR interval (RRI) and systolic blood pressure (SBP) before and after head-up tilt (HUT) with different tilt speeds from dynamic and steady perspectives. The data used was from database Physiologic Response to Changes in Posture(PRCP) published on PhysioNet, providing documentary ECG and continuous arterial blood pressure signals of ten healthy subjects (5 males and 5 females) during HUT stimulation. Beat-by-beat time series of RRI and SBP were extracted from bothslow tilt (ST,75°HUT over 50 s) and rapid tilt (RT,75°HUT over 2 s). Then, time-frequency analysis and information decomposition analysis, combined with time-domain indexes and short-term fractal exponent (α1) were applied to perform joint analysis between RRI and SBP. The results of information decomposition analysis indicated that all of the significant differences appeared in the feedback direction (SBP→RRI)due to baroreflex control on RRI. The prediction of RRI after ST significantly increased compared to that in supine position (0.416±0.067 vs 0.626±0.127), indicating the elevation of the couplingstrength along the baroreflex. However, HUT showed few effects in the feedforward direction of RRI→SBP. There were no significant differences between ST and RT for all of the same indexes before HUT. However, the coefficient of variation of RRI (CVRRI) in the steady state after RT was significantly increased and α1 was significantly decreased compared to that after ST despite the fact that there was no difference for RRI. What’s more, the results of time-frequency analysis suggested the different behavior of dynamic response to ST and RT. Our research proved the effectiveness of information decomposition analysis to detect the dominant causal direction (feedback or feedforward) in the RRI-SBP interactions and to characterize the changes of the prediction of RRI and SBP signal before and after HUT. 2017 Vol. 36 (3): 284-292 [Abstract] ( 297 ) HTML (1 KB)  PDF (1341 KB)  ( 503 ) 293 Algorithm of Left Bundle Branch Block Diagnosis Based on ELM Wang Zhiqiong, Wu Chengyang, Xin Junchang, Zhao Yue, Li Xiang DOI: 10.3969/j.issn.0258-8021.2017.03.005 As a common clinical arrhythmia, left bundle branch block is a signal of left ventricular systolic function decreased and mortality increased in patients, machine learning algorithm aided diagnosis of the disease will play a positive role in detection and diagnosis. Currently, left bundle branch block automatic identification mode is still using support vector machines and other traditional machine learning algorithms for training and testing, these traditional neural network algorithms prone to local optimal solution, which is not suitable to classified LBBB. Herein, this paper proposed an algorithm about automatic diagnosis of left bundle branch block based on ELM. Firstly, the ECG signal was preprocessed, including the removal of baseline drift, high-frequency noise and power-line interference; then, we created the model by features of LBBB such as the length of QRS after the location of QRS-T wave was determined. Finally, we provided the LBBB diagnosis algorithm based on ELM. Additionally, we tested 5000 groups of data in MIT_BIH. Results showed the algorithm was effective in noise removal and wave extraction. ELM was 88.5% that is shorter than SVM in training time, and ELM had improvement of 2.4%, 5.4%, 1.2%, 3.6%, 2% in time, accuracy, sensitivity, specificity, FP ratio and FN ratio respectively. Accordingly, ELM had more advantages in LBBB diagnosis. 2017 Vol. 36 (3): 293-299 [Abstract] ( 361 ) HTML (1 KB)  PDF (1113 KB)  ( 525 ) 300 Research of Mitral Valve Model in the 0D Left Ventricular Circulation System Zhang Guijie, Wang Hao, Jing Teng, He Zhaoming DOI: 10.3969/j.issn.0258-8021.2017.03.006 This study presented a leaflet motion resistance model of the mitral valve that could simulate the mitral valve dynamics accurately. This model had a variable resistance based on mitral valve leaflet opening angle θ and involved the dynamic control equation of the mitral valve movement and main factors affecting the movement of the leaflets:transvalvular pressure and the blood flow force when it applied in the 0-D lumped parameter model of left heart circulation system, the hemodynamics were derived. The results of this model and step-function with instant valve closure and empirically specified time-varying resistance models were compared under the same cardiac output and regurgitation in left ventricular blood circulation. The leaflet motion resistance model reflected the hemodynamics of the closing process, including the delayed blood flow behind pressure and closing volume. In addition, the model allowed adjustment of the time required for valve opening and closing by changing the impact coefficients of moment of inertial of the leaflet, transvalvular pressure and blood flow-rate, the time of valve opening and closing were 50.0 ms and 40.2 ms. The model eliminated the shortcomings of ignoring leaflet motion of the step-function resistance model and avoided the irrational starting time of valve closing of the time-varying resistance model. The model simulated the mitral valve dynamics accurately and was easy to control. 2017 Vol. 36 (3): 300-307 [Abstract] ( 356 ) HTML (1 KB)  PDF (987 KB)  ( 376 ) 308 Numerical Simulation and Experiment for Diffusion and Deposition of Aerosol in Realistic Human Upper Respiratory Tract under the Effect of Fluid-Solid Interaction Xu Xinxi, Sun Dong, Zhao Xiuguo, Li Fusheng, Liu Yajun DOI: 10.3969/j.issn.0258-8021.2017.03.007 The diffusion and deposition of aerosol in human upper respiratory tract was simulated by using the large eddy simulation method and Lagrangian stochastic trajectory model with 3D standardized model of realistic human upper respiratory tract under the fluid-solid interaction and cyclic respiratory pattern. The influence of vortex evolution on the diffusion of aerosol was analyzed and the deposition fraction of aerosol in human upper respiratory tract was measured, which verified that the numerical simulation method was accurate and reasonable. The results showed that the aerosol particles with size of 0.3 μm were more likely to pass through the upper respiratory tract and move into the lower bronchus than the particles with size of 6.5 μm in the phase of inhalation. The aerosol particles entering into the upper tract by the exhalation flow returned, convoluted or deposited in the tract and some of the aerosol particles were taken out of mouth during the exhalation. The deposition fraction of the aerosol particles with sizes of 0.3 μm and 6.5 μm was high in throat and trachea, and low in the mouth. The deposition fraction of the aerosol particles with size of 6.5 μm in different zones of the upper respiratory tract was obviously higher than that with size of 0.3 μm. With the fluid-solid interaction, the deposition fraction of aerosol particles decreased due to the airflow impact cushioning caused by the deformation of respiratory tract. The mechanism of deposition for the larger aerosol particles was inertial impaction, and the deposition for the smaller aerosol particles was more likely to be affected by the turbulent dispersion and entrainment of eddy current. 2017 Vol. 36 (3): 308-315 [Abstract] ( 307 ) HTML (1 KB)  PDF (6925 KB)  ( 312 ) 316 The Effect of Different Curvature on the Distribution of Nitric Oxide Concentration in the Curved Arterial Segment Zhao Hongjun, Han Jintao, Liu Cong, Dov Jaron, Qiao Huiting DOI: 10.3969/j.issn.0258-8021.2017.03.008 Nitric oxide (NO) produced by the endothelium plays an important role in regulating vascular tone. However, the effect of different curvature on the distribution of NO concentration in the curved arterial segment has not been clear. We developed eleven mass transport models with different curvature to simulate the distributions for NO in blood, vascular walls and surrounding tissue. Results showed that the radical distribution of NO was uneven in the curved segment. The outer concentration was higher than the inner one. And the concentration difference increased and then decreased with the increased curvature. In the smooth muscle region, the concentration difference reached the maximum when the curved height was increased to 2mm under the condition of the vessel projection length was a constant (20 mm),where the curvature was increased to 0.04,the outer boundary concentration was 23.74% higher than the inner one. This study revealed the effect of different curvature on NO concentration, and suggested that the uneven distribution of NO might cause vascular morphology changes and lead to vascular disease. Those models may provide a theoretical support for the further research and vascular disease risk assessment. 2017 Vol. 36 (3): 316-321 [Abstract] ( 313 ) HTML (1 KB)  PDF (2776 KB)  ( 306 ) 322 Automatic Test System for Electro-Acoustic Conversion Efficiency of Focused Ultrasonic Transducer Based on Virtual Instrumentation Technology Liu Yang, Tan Jianwen, Zeng Deping, Zhong Zhiming, Chen Zhicong DOI: 10.3969/j.issn.0258-8021.2017.03.009 Focused ultrasound transducer is the core of ultrasound therapy device, and the electro-acoustic conversion efficiency is one of the most important indexes to evaluate the performance of the transducer. In practical working conditions, the electro-acoustic conversion characteristic is often used to determine the operating frequency and driving parameters of therapy system. Therefore, the high accuracy, efficiency and convenience of the electro-acoustic conversion characteristics test system are needed. To solve this problem, an automatic test system was constructed in this work. The electrical power meter based on directional couplers was used to measure the input electrical power of the transducer. The acoustic output power of the transducer was measured by radiation force balance. The automatic test software on master computer was developed based on virtual instrumentation technology. It can collect and process the measured data in real time. Based on the developed automatic test system, the electro-acoustic conversion efficiency of a transducer was tested at different frequencies and driving power. The stability of the system was analyzed by the coefficient of variation and compared with the manual test. The results showed that the test system had good accuracy, the single test time was shortened more than 5 times. Under the driving power of 10 W, 20 W and 30 W, the automatic test system (the variable coefficient were 4.06%, 4.31%, 4.65%) was more stable than that manual test (the variable coefficient were 4.14%, 4.69%, 5.83%, respectively), which met the application requirements of the test system. 2017 Vol. 36 (3): 322-328 [Abstract] ( 371 ) HTML (1 KB)  PDF (4169 KB)  ( 510 ) 329 An Intelligent Support System for Patient Safety Checklists Nan Shan, Lu Xudong, Yang Zhixiang, Liu Yuqi, Chen Yundai, Duan Huilong DOI: 10.3969/j.issn.0258-8021.2017.03.010 Safety checklists have gain increasingly attention in recent years as an effective way of standardizing healthcare. They serve as a quality improving tool by enabling providers checking the variance between the actual situation and the best practice prior to the critical activities. However, the traditional checklists in paper form are lack of integration with clinical workflow, specification to individual patients and information system support, which increases the workload of providers and leads to ineffective implementation. This study decomposed safety checklist knowledge into 4 layers, i.e. clinical workflow, checklist form, medical algorithm and supplementary information, aiming to make checklists adjustable and executable by computerized systems. A support system had been developed according to the checklist representation and execution mechanism. The system was able to reduce the providers' workload by integrating checklist into the daily care process of providers for individual patients and providing related patient data and knowledge. A percutaneous coronary intervention peri-operative checklist set had been used to validate the proposed system. By using the system, the process was decomposed into 11 scenarios integrated with the actual clinical workflow. In each scenario, a group of clinical algorithms was applied to produce checkable items. The results indicated that the proposed approach effectively supported the representation and execution of checklists and providers could have benefit from the system by using the process-oriented and patient-specific checklists. 2017 Vol. 36 (3): 329-335 [Abstract] ( 343 ) HTML (1 KB)  PDF (3135 KB)  ( 352 ) 336 Evaluation of Cytotoxicity of Nano Titanium Dioxide Based on Cole-Cole Model Bao Xiuling, Liao Cong, Ma Qing DOI: 10.3969/j.issn.0258-8021.2017.03.011 The aim of this work is to evaluate the cytotoxicity of titanium dioxide nanoparticles (Nano-TiO2) at different doses based on Cole-Cole model and explore the electrophysiological mechanism. The human gastric cancer cell MGC803 was exposed to 150 mg/L and 300 mg/L Nano-TiO2 suspension for 24 h. The amplitude and phase angle of the impedance of human gastric cancer MGC803 cell suspension were measured by 4294A Agilent precision impedance analyzer in the range of 1 kHz-100 MHz. Based on the residual analysis of the curve fitting of the electrical impedance spectroscopy and the Nyquist plot, the parameters of the Cole-Cole model were established, and the effect of Nano-TiO2 on the conductivity of MGC803 cells was evaluated based on the Cole-Cole model. Results showed that 150 mg/L and 300 mg/L of Nano-TiO2 induced the first impedance increment (ΔZ1) decreased 18.18% (P<0.001) and 39.39% (P<0.001) respectively, the second impedance increment (ΔZ2) decreased 6.56% (P<0.001) and 8.2% (P<0.001) respectively, and reduced the resistance of cellular membrane and nuclear membrane of MGC803 cells, increased its conductivity. The first characteristic frequency (fC1) was increased by 19.74% (P<0.001) and 29.67% (P<0.001) respectively, and second characteristic frequency (fC2) was increased by 6.28% (P<0.001) and 23.43% (P<0.001) respectively. The first dispersion angle (β1) was reduced by 1.35% (P>0.05) and 2.70% (P<0.05), respectively. The Cole-Cole model can be applied to evaluate the role of Nano-TiO2 and explain its electrophysiological mechanism, providing a method for the study of cytotoxicity of nanoparticles. 2017 Vol. 36 (3): 336-341 [Abstract] ( 348 ) HTML (1 KB)  PDF (2446 KB)  ( 272 )        Reviews 342 The Neuroimage Research Progress of Psychiatric Comorbidities in Epilepsy He Zhongqiong, Yu Liang, Jiang Yuchao, BenjaminKlugah-Brown, Luo Cheng, Yao Dezhong DOI: 10.3969/j.issn.0258-8021.2017.03.012 Psychiatric comorbidities in epilepsy is a common mental disorder, but the mechanisms of those disorders are indefinite, and some patients are disturbed by this disease time and again, which greatly affects the quality of life in patients. The technologies of neuroimaging provide a unique approach to studying the abnormal cerebral structure and function. This article is to review recent studies of psychiatric comorbidities in epilepsy based on depression in people with epilepsy, anxiety in people with epilepsy, schizophrenia-like psychosis of epilepsy and attention deficit- hyperactivity disorder (ADHD) in people with epilepsy, aiming to expand the way of thinking about and understanding in clinical researches and in exploring mechanisms of psychosis of epilepsy. 2017 Vol. 36 (3): 342-347 [Abstract] ( 391 ) HTML (1 KB)  PDF (773 KB)  ( 415 ) 348 The Research Progress of Magnetic Fe3O4/Mesoporous Silica Composite Microspheres Nie Libo, Yang Hongcheng, Jiang Pengfei DOI: 10.3969/j.issn.0258-8021.2017.03.013 Magnetic Fe3O4/mesoporous silica (Fe3O4/mSiO2) composite microspheres combine the advantage of magnetism performance of Fe3O4 nanoparticles and the space loading capacity of mesoporous silica, which therefore are widely explored for uses in biomedicine. In this paper the synthetic methods of Fe3O4/mSiO2 composite microspheres such as core-shell type, hollow type and rattle type were introduced. The applications of Fe3O4/mSiO2 composite microspheres in targeting drug-loading system, magnetic resonance imaging (MRI), magnetic mediated hyperthermia drug-loading system and biological separation are summarized as well. 2017 Vol. 36 (3): 348-353 [Abstract] ( 358 ) HTML (1 KB)  PDF (2526 KB)  ( 613 ) 354 Progress and Challenges of Bioresorbable Vascular Scaffolds Ren Hao, Li Rongke, Wang Ren DOI: 10.3969/j.issn.0258-8021.2017.03.014 Although drug-coating technologies have made stent achieve a great progress, and the application of drug-coating stents is more than that of non-drug coating stents in clinical application. However, the long-term efficacy still required further observation and verification. Regardless of what types of drug-coating stents, when the stent was implanted in the body for a long time, the drug coating would be gradually absorbed and the bare stent was exposed to the blood and the vein wall, therefore, the problems of the non-drug coating stents can not be completely solved. Bioresorbable stents are different from the non-degradable stents, they can be degraded when implanted in the human body. After a period of time, it is degraded completely and excreted. This paper not only described various bioresorbable stents, including polymer, magnesium alloy, pure iron, zn-alloy, but also analyzed existing problems, aiming to make a contribution to the development and application of bioresorbable stents. 2017 Vol. 36 (3): 354-359 [Abstract] ( 402 ) HTML (1 KB)  PDF (749 KB)  ( 527 )        Communications 360 A Multi-functional Cardiopulmonary Sound Electronic Stethoscope Huang Mei, Liu Hongying, Pi Xitian, Ao Yilu, Wang Zi DOI: 10.3969/j.issn.0258-8021.2017.03.015 2017 Vol. 36 (3): 360-364 [Abstract] ( 353 ) HTML (1 KB)  PDF (3043 KB)  ( 565 ) 365 Three Dimensional Finite Element Simulation of Thyroplasty Hu Binbin, Shi Tingchun, Lin Zhihong DOI: 10.3969/j.issn.0258-8021.2017.03.016 2017 Vol. 36 (3): 365-369 [Abstract] ( 337 ) HTML (1 KB)  PDF (8212 KB)  ( 186 ) 370 Biomechanical Consequences of Different Step-Off Displacement of Both-Column Acetabular Fractures Dong Yilong, Huang Xiangxiang, Qian Yuenan, Liu Liangle, Zhang Yuanxun, Zhong Xiqiang, Cai Chunyuan DOI: 10.3969/j.issn.0258-8021.2017.03.017 2017 Vol. 36 (3): 370-374 [Abstract] ( 279 ) HTML (1 KB)  PDF (2406 KB)  ( 406 ) 375 The Stability Study of Thoracic Pedicle Srew Instrumentation with Different Degree of Posterior Cortex Bitten away Liu Liangle, Dai Minghai, Dong Yilong, Liu Min, Zhong Xiqiang, Tang Chengxuan DOI: 10.3969/j.issn.0258-8021.2017.03.018 2017 Vol. 36 (3): 375-379 [Abstract] ( 260 ) HTML (1 KB)  PDF (5496 KB)  ( 367 ) 380 The Advanced Method of Kidney and Lung De-Cellularized Scaffold through in vitro Perfusion Chen Pianpian, Lin Qian, Zhu Qunyan, Zhao Yingzheng DOI: 10.3969/j.issn.0258-8021.2017.03.019 2017 Vol. 36 (3): 380-384 [Abstract] ( 305 ) HTML (1 KB)  PDF (11377 KB)  ( 102 )

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