The peak period of cardiovascular disease (CVD) is around the time of awakening in the morning, which may be related to the surge of sympathetic activity at the end of nocturnal sleep. This paper chose 140 participants as study object, 70 of which had occurred CVD events while the rest hadn’t during a two-year follow-up period. A two-layer model was proposed to investigate whether hypnopompic heart rate variability (HRV) was informative to distinguish these two types of participants. In the proposed model, the extreme gradient boosting algorithm (XGBoost) was used to construct a classifier in the first layer. By evaluating the feature importance of the classifier, those features with larger importance were fed into the second layer to construct the final classifier. Three machine learning algorithms, i.e., XGBoost, random forest and support vector machine were employed and compared in the second layer to find out which one can achieve the highest performance. The results showed that, with the analysis of hypnopompic HRV, the XGBoost+XGBoost model achieved the best performance with an accuracy of 84.3%. Compared with conventional time-domain and frequency-domain features, those features derived from nonlinear dynamic analysis were more important to the model. Especially, modified permutation entropy at scale 1 and sample entropy at scale 3 were relatively important. This study might have significance for the prevention and diagnosis of CVD, as well as for the design of CVD-risk assessment system.
This study aims to optimize surface electromyography-based gesture recognition technique, focusing on the impact of muscle fatigue on the recognition performance. An innovative real-time analysis algorithm is proposed in the paper, which can extract muscle fatigue features in real time and fuse them into the hand gesture recognition process. Based on self-collected data, this paper applies algorithms such as convolutional neural networks and long short-term memory networks to provide an in-depth analysis of the feature extraction method of muscle fatigue, and compares the impact of muscle fatigue features on the performance of surface electromyography-based gesture recognition tasks. The results show that by fusing the muscle fatigue features in real time, the algorithm proposed in this paper improves the accuracy of hand gesture recognition at different fatigue levels, and the average recognition accuracy for different subjects is also improved. In summary, the algorithm in this paper not only improves the adaptability and robustness of the hand gesture recognition system, but its research process can also provide new insights into the development of gesture recognition technology in the field of biomedical engineering.
Committee of Minimally Invasive Cardiovascular Surgery (CMICS) annually investigates the minimally invasive cardiovascular surgery performed by departments of cardiovascular surgery of all hospitals in China of last year, and makes classification and summary according to the operation amount of minimally invasive surgery, regional and hospital distribution, and publishes it on the theme report of China Minimally Invasive Cardiovascular Surgery Conference (CMC). In 2021, CMICS published the 2018-2019 annual data of Chinese cardiovascular surgery in the form of a white paper for the first time in the Chinese Journal of Clinical Thoracic and Cardiovascular Surgery, which attracted great attention from peers. In this statistical report, CMICS will focus on the volume of minimally invasive cardiovascular surgery, regional and hospital distribution in China (excluding Hong Kong Special Administrative Region, Macao Special Administrative Region, and Taiwan Province) in the 2020—2021 for your reference.
Objective To investigate the etiological diagnosis of chronic cough with pharyngitis-like manifestations. Methods Patients with chronic cough and pharyngitis-like manifestations were recruited from Outpatient Department of Guangzhou Institute of Respiratory Diseases between December 2002 to March 2010. The causes of chronic cough were investigated using a well-established diagnostic protocol, including history taking and physical examination, pulmonary function tests, induced sputum cytology, 24-h esophageal pH monitoring, etc. The final diagnosis depended on clinical manifestations, examination findings, and a successful response to therapy. Results 326 patients with chronic cough and pharyngitislike manifestations were included in the study with amedian duration of 24 ( 2 ～480) months, amean age of 41 ±13 years. The causes of chronic cough were identified as follows: post nasal drip syndrome or upper airway cough syndrome in 73 cases ( 23. 31% ) , cough variant asthma in 61 cases( 18. 71% ) , eosinophilic bronchitis in 70 cases( 22. 47% ) , gastroesophageal reflux-induced cough in 54 cases ( 16. 56% ) , atopiccough in 48 cases ( 14. 72% ) , and others in 40 cases ( 12. 27% ) . There is no significant difference in percentage of common causes of chronic cough ( P gt; 0. 05) . Conclusion The proportions of upper airway syndrome and other common causes are similar in chronic cough with pharyngitis-like manifestatioins, whichsuggest pharyngitis-like manifestations are not specific for diagnosis of upper airway cough syndrome.
Objective To observe the effect of epidermal growth factor (EGF) on the proliferation, adhesion, invasiveness and the activation of nuclear factor-κB (NF-κB), matrix metalloproteinases (MMPs) expression and explore related mechanisms in pancreatic cancer cells. Methods Cell invasion assay, proliferation assay and adhesion assay were used to examine the proliferation, adhesion and invasiveness of pancreatic cancer cells, respectively. NF-κB activity was detected by electrophoretic mobility shift assay (EMSA), and MMPs protein and mRNA expressions were investigated by gelatin zymography, Western blot and reverse transcriptase-polymerase chain reaction (RT-PCR). Results EGF increased the invasiveness of pancreatic cancer cell in a dose-dependent manner (P＜0.05), but did not affect cell proliferation or adhesion. The expressions of MMP-9 mRNA and protein significantly increased after induction by EGF and were highest when EGF concentration was 50 ng/ml, while there was no effect on the expressions of MMP-2 mRNA and protein. Furthermore, NF-κB activity increased with increased concentration of EGF in a concentration-dependent manner (P＜0.05). In addition, NF-κB activity and the expressions of MMP-9 mRNA and protein by pretreatment with both pyrrolidine dithiocarbamate (PDTC) and EGF decreased when compared that by pretreatment with EGF alone. The invasiveness of pancreatic cancer cell by pretreatment with both PDTC and EGF decreased when compared that by pretreatment with EGF alone and nothing (P＜0.05).Conclusion The findings indicate that the NF-κB-mediated MMP-9 induction is essential for EGF-induced invasiveness in pancreatic cancer cells, which can be inhibited by PDTC.
ObjectiveTo discuss the feasibility of establishment of animal model of "functional" bicuspid aortic valve with swine and observe its effect on the wall shear stress inside the aorta. MethodsFour common Shanghai White Swine with body weight between 50 kg to 55 kg were selected. Under general anesthesia and cardiopulmonary bypass, the aortic transverse incision approach was used, continuous suture with 6-0 polypropylene to align the left and right coronary valve leaflets to create a bicuspid valve morphology. After the operation, echocardiography was used to observe the aortic valve morphology and the hemodynamic changes of the aortic valve orifice. The effect on the wall shear stress inside the aorta was studied with 4D-Flow magnetic resonance imaging (MRI). ResultsA total of 4 swine "functional" bicuspid aortic valve models were established, with a success rate of 100.0%. Echocardiography showed that the blood flow velocity of the aortic valve orifice was faster than that before the operation (0.96 m/s vs. 1.80 m/s). 4D-Flow MRI showed abnormally increased wall shear stress and blood flow velocity in the aorta of the animal models. After the surgery, in model animals, the maximal wall shear stress inside the ascending aorta was greater than 1.36 Pa, and the maximum blood flow velocity was greater than 1.4 m/s. ConclusionEstablishment of the animal model of "functional" bicuspid aortic valve in swine is feasible, scientific and reliable. It can be used in researches on evaluating the pathophysiological changes.
The minimally invasive cardiovascular surgery developed rapidly in last decades. In order to promote the development of minimally invasive cardiovascular surgery in China, the Chinese Minimally Invasive Cardiovascular Surgery Committee (CMICS) has gradually standardized the collection and report of the data of Chinese minimally invasive cardiovascular surgery since its establishment. The total operation volume of minimally invasive cardiovascular surgery in China has achieved substantial growth with a remarkable popularization of concepts of minimally invasive medicine in 2019. The data of Chinese minimally invasive cardiovascular surgery in 2019 was reported as a paper for the first time, which may provide reference to cardiovascular surgeons and related professionals.