1. Risk factor analysis of perioperative complications in patients with radical gastrectomy for gastric cancer
Peng ZHANG ; Tianheng LAN ; Yiming ZHOU ; Jianping DENG ; Chengzhi WEI ; Gonghe WANG ; Lei TIAN
Chinese Journal of Gastrointestinal Surgery 2019;22(8):736-741
Objective:
To identify the risk factors of perioperative complications after radical gastrectomy for gastric cancer.
Methods:
A retrospective case-control study was performed. Case inclusion criteria: (1) patients undergoing radical gastrectomy (D2); (2) primary gastric cancer without distant organ metastasis confirmed by postoperative pathology; (3) no neoadjuvant chemotherapy before surgery. Patients with peritoneal tumor dissemination found during operation, undergoing palliative operation due to distant metastasis, and undergoing combined organ resection and those without complete clinicopathological data were excluded. According to the above criteria, 426 patients with gastric cancer at our department from January 2015 to June 2017 were included in this study. Of 426 patients, 285 were male and 141 were female with a mean age of (55.4±9.7) years. According to the "Japan Clinical Cancer Research Group (JCOG) classification criteria for postoperative complications of gastric cancer", patients with grade II and higher complications were classified as complication group, and patients with no complication or grade I complication were classified as non-complication group. Baseline data were compared between two groups. Associations of perioperative complication with gender, age, body mass index, preoperative routine laboratory test, American Society of Anesthesiologists (ASA) classification, activities of daily living (ADL) assessment, past medical history as well as preoperative conditions (hypertension and/or diabetes), surgical resection procedure, incision type, operation time, intraoperative blood loss/body mass ratio were examined. Univariate analysis was performed using χ2 test and the Wilcoxon rank sum test to screen the statistically significant variables associated with perioperative complications. The significant variables were included in multivariate logistic regression analysis to identify risk factors of perioperative complication.
Results:
Grade II or higher complications after surgery were developed in 97 patients (22.8%), which included anastomotic leakage in 18 cases (4.2%), postoperative bleeding in 9 cases (2.1%), abdominal abscess in 5 cases (1.2%), intestinal obstruction in 5 cases (1.2%), pancreatic leakage in 1 case (0.2%), and other adverse events in 59 cases (13.8%). Univariate analysis suggested that the gender, age, ADL, incision type, intraoperative blood loss/body mass ratio, and operation time were associated with perioperative complication (all
2.Effects of virtual reality visual experience on brain functional network.
Tianheng ZHANG ; Lei WANG ; Miaomiao GUO ; Guizhi XU
Journal of Biomedical Engineering 2020;37(2):251-261
With the wide application of virtual reality technology and the rapid popularization of virtual reality devices, the problem of brain fatigue caused by prolonged use has attracted wide attention. Sixteen healthy subjects were selected in this study. And electroencephalogram (EEG) signals were acquired synchronously while the subjects watch videos in similar types presented by traditional displayer and virtual reality separately. Two questionnaires were conducted by all subjects to evaluate the state of fatigue before and after the experiment. The mutual correlation method was selected to construct the mutual correlation brain network of EEG signals before and after watching videos in two modes. We also calculated the mutual correlation coefficient matrix and the mutual correlation binary matrix and compared the average of degree, clustering coefficient, path length, global efficiency and small world attribute during two experiments. The results showed that the subjects were easier to get fatigue by watching virtual reality video than watching video presented by traditional displayer in a certain period of time. By comparing the characteristic parameters of brain network before and after watching videos, it was found that the average degree value, the average clustering coefficient, the average global efficiency and the small world attribute decreases while the average path length value increased significantly. In addition, compared to traditional plane video, the characteristic parameters of brain network changed more greatly after watching the virtual reality video with a significant difference ( < 0.05). This study can provide theoretical basis and experimental reference for analyzing and evaluating brain fatigue induced by virtual reality visual experience.
Brain
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physiology
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Electroencephalography
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Healthy Volunteers
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Humans
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Mental Fatigue
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Virtual Reality
3.Analysis of time-frequency characteristics and coherence of local field potentials during working memory task of rats after high-frequency repeated transcranial magnetic stimulation.
Guizhi XU ; Ning WANG ; Miaomiao GUO ; Tianheng ZHANG ; Yuming TONG
Journal of Biomedical Engineering 2020;37(5):756-764
Repetitive transcranial magnetic stimulation(rTMS) is a painless and non-invasive method for stimulation and modulation in the field of cognitive neuroscience research and clinical neurological regulation. In this paper, adult Wistar rats were divided into the rTMS group and control group randomly. Rats in the rTMS group were stimulated with 5 Hz rTMS for 14 days, while the rats in the control group did not accept any stimulation. Then, the behavior and local field potentials (LFPs) were recorded synchronously when the rats perform a working memory (WM) task with T-maze. Finally, the time-frequency distribution and coherence characteristics of the LFPs signal in the prefrontal cortex (PFC) during working memory task were analyzed. The results showed that the rats in the rTMS group needed less training days to reach the task correction criterion than the control group (
Animals
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Memory, Short-Term
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Neurons
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Prefrontal Cortex
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Rats
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Rats, Wistar
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Transcranial Magnetic Stimulation