BACKGROUND:Digital three-dimensional model which can reflect the fine structure of the chambers inside heart not only enhances the understanding of cardiac physiology, but also provides basic medical data for the study of cardiac electrophysiology simulation and endocardial electrophysiological mapping navigation. OBJECTIVE:To construct the digital three-dimensional model of cardiac cavity from sectional data and in conformity with the actual anatomical structure. METHODS:Image segmentation was accomplished in MATLAB environment. Firstly, registration of human cardiac cavity slice dataset was realized. Secondly, classifying each composition was achieved by clustering method according to color characteristics of the image. Then, both cardiac cavity and related connected region was distinguished by region growing method. At last, the processed image was reconstructed through dedicated medical processing software into three-dimensional model of the cardiac cavity. RESULTS AND CONCLUSION:The proposed method could reconstruct quite exquisite three-dimensional model of the cardiac cavity. In models, left and right atrial and ventricular structure was clear. Aorta and superior vena cava were visible. Three tricuspid and mitral valve were also observed. Results indicated that reconstructed model can reflect the anatomical characteristics of cardiac cavity accurately, and provide basic medical data for the study on electrophysiological simulation and endocardial electric mapping.

In order to enhance the position accuracy of ablation catheter in heart electrophysiology operation, signals of respiration and heartbeat must be removed for subsequent data processing. Based on locating principle of electrical field with low frequency, synchronous detector with MC1496 has been developed in this study. In the present research, several methods are utilized to optimize the circuit performance, such as coupling and stopping direct current, low-pass filtering, as well as limiting ripple voltage etc. Through simulation results, it showed that the demodulation performance of the circuit was fine. Through simulation platform of thorax electric field and animal experiment, the circuit feasibility were further proved good for extracting signals of respiration and heartbeat.
Atrial Fibrillation ; surgery ; Catheter Ablation ; methods ; Computer Simulation ; Electromagnetic Fields ; Heart ; anatomy & histology ; physiology ; Humans ; Models, Biological ; Signal Processing, Computer-Assisted ; Thorax

Objective To analyze the mortality risk and evaluate the curative effects of surgery and non-surgery on NSCLC with diameter > 7.0 cm. Methods We collected the data of NSCLC patients with diameter > 7.0 cm from 2010 to 2015 from the SEER database. The 1, 2, 3-year survival rates were analyzed by life table method. Overall survival curve was estimated by Kaplan-Meier method. Univariate and multivariate Cox regression models were used to analyze the independent prognostic factors. Results The 1, 2, 3-year survival rates were 51.8%, 33.0% and 25.0%, respectively. In univariate and multivariate analyses, tumor size, N stage and treatment were the independent prognostic factors (P < 0.001). Conclusion Surgery is benefited for the prognosis of stage N0-N1 NSCLC patients with diameter > 7.0 cm. And for stage N2 NSCLC patients with diameter 7.0-9.0 cm, surgical treatment has advantages in improving the prognosis. Surgical and non-surgical patients with tumor diameter ≥9.0 cm or lymph node N3 stage have no statistically significant differences in prognosis. In addition, palliative treatment does not improve the prognosis of patients.

Acetaldehyde dehydrogenase 2 (ALDH2) is an important kind of aldehyde dehydrogenase in mitochondria, which has the function of eliminating acetaldehyde and other toxic aldehydes substances. Furthermore, it is abundant in liver and is closely related to the occurrence and development of a variety of liver diseases. ALDH2 genetic polymorphisms plays an important role in the occurrence of a variety of liver diseases in the human population.This paper mainly reviews the research progress of ALDH2 in liver diseases in recent years, with a view to provide theoretical basis for clinical prevention and treatment.