ABSTRACT
Objective: To explore the early predictors and their predicting value of 28-day mortality in sepsis patients and to investigate the possible causes of death. Methods: 127 sepsis patients were included, including 79 cases in the survival group and 48 cases in the death group. The results of all patients on admission were recorded. After screening the risk factors of 28-day mortality, the receiver operating characteristic curve (ROC) was used to determine their predictive value for the 28-day mortality rate on admission, and the Kaplan-Meier curve was drawn to compare the 28-day mortality rate between groups. Finally, patients with cytokine and lymphocyte subsets results were included for investigating the possible causes of death through correlation analysis. Results: APACHE II (acute physiology and chronic health evaluation II), SOFA (Sequential Organ Failure Assessment) and red blood cell distribution width (RDW) were the risk factors for 28-day mortality in sepsis patients (OR: 1.130 vs.1.160 vs.1.530, P < 0.05). The area under the curve (AUC), sensitivity and specificity of APACHE II, SOFA and RDW in predicting the mortality rate at 28 days after admission in sepsis patients were 0.763 vs 0.806 vs 0.723, 79.2% vs 68.8% vs 75.0%, 65.8% vs 89.9% vs 68.4%. The combined predicted AUC was 0.873, the sensitivity was 89.6%, and the specificity was 82.3%. The Kaplan-Meier survival curve showed that the 28-day mortality rates of sepsis patients with APACHE II≥18.5, SOFA≥11.5 and RDW≥13.8 were 58.5%, 80.5% and 59.0%, respectively. In the death group, APACHE II was positively correlated with SOFA, IL-2, and IL-10, and RDW was positively correlated with PLT, TNF-α, CD3+ lymphocyte count, and CD8+ lymphocyte count. Conclusion: Sepsis patients with high APACHE II, SOFA and RDW levels at admission have an increased 28-day mortality rate. The elevation of these indicators in dead patients are related to immune dysfunction.
ABSTRACT
The phase sensitive optical time-domain reflectometer (φ-OTDR), or in some applications called distributed acoustic sensing (DAS), has been a popularly used technology for long-distance monitoring of vibrational signals in recent years. Since φ-OTDR systems usually operate in complicated and dynamic environments, there have been multiple intrusion event signals and also numerous noise interferences, which have been a major stumbling block toward the system's efficiency and effectiveness. Many studies have proposed different techniques to mitigate this problem mainly in φ-OTDR setup upgrades and improvements in data processing techniques. Most recently, machine learning methods for event classifications in order to help identify and categorize intrusion events have become the heated spot. In this paper, we provide a review of recent technologies from conventional machine learning algorithms to deep neural networks for event classifications aimed at increasing the recognition/classification accuracy and reducing nuisance alarm rates (NARs) in φ-OTDR systems. We present a comparative analysis of the current classification methods and then evaluate their performance in terms of classification accuracy, NAR, precision, recall, identification time, and other parameters.
ABSTRACT
OBJECTIVE: To investigate the role of mitochondrial permeability transition pore (MPTP) opening in mediating the effect of endomorphine-1 postconditioning to alleviate myocardial ischemia-reperfusion (IR) injury in rats. METHODS: Forty-five male SD rats were randomized equally for sham operation, myocardial IR injury, endomorphin-1 postconditioning, atractyloside (a MPTP opener) postconditioning, or endomorphin-1 + atractyloside postconditioning. The hemodynamic param-eters of the rats were monitored in real time via carotid artery cannulation to the left ventricle. After reperfusion, plasma samples were collected for biochemical analyses. The size of myocardial infarct area was detected using Evans blue and TTC double staining, and the myocardial expressions of apoptosis-related proteins Bax, Bcl-2 and cleaved caspase-3 were analyzed using Western blotting. RESULTS: Myocardial IR injury resulted in significantly decreased heart rate and blood pressure in the rats (P<0.05). Compared with those in IR group, the rats with endomorphin-1 postconditioning showed significantly increased heart rate and blood pressure (P<0.05), lowered contents or activities of LDH, CK-MB, cTnI, IL-6, TNF-α, Cyt-C and MDA in the plasma (P<0.05), increased plasma SOD activity (P<0.05), reduced size of myocardial infarction, decreased myocardial expression of Bax and cleaved caspase-3 protein (P<0.05), and increased myocardial expression of Bcl-2 protein (P<0.05). All these changes induced by endomorphin-1 were obviously reversed by atractyloside postconditioning (P<0.05). CONCLUSION: Endomorphin-1 postconditioning protects against myocardial IR injury in rats probably by inhibiting the opening of MPTP and reducing cardiac myocyte apoptosis via down-regulating cleaved caspase-3 expression.
