Predictive value of neutrophil/lymphocyte ratio on myocardial injury in severe COVID-19 patients / 中华心血管病杂志

Objective: To explore the predictive value of neutrophil/lymphocyte ratio (NLR) on myocardial injury in severe COVID-19 patients. Methods: In this single-center retrospective cohort study, we collected and analyzed data form 133 severe COVID-19 patients admitted to Renmin Hospital of Wuhan University (Eastern District) from January 30 to February 18, 2020. Patients were divided into myocardial injury group (n=29) and non-myocardial injury group (n=104) according the presence or absence of myocardial injury. The general information of patients was collected by electronic medical record database system. All patients were followed up for 30 days, the organ injury and/or dysfunction were monitored, the in-hospital death was compared between the two groups, and the disease progression was reevaluated and classified at 14 days after initial hospitalization. Logistic regression analysis was performed to identify risk factors of myocardial injury in severe COVID-19 patients. The ROC of NLR was calculated, and the AUC was determined to estimate the optimal cut-off value of NLR for predicting myocardial injury in severe cases of COVID-19. Results: There was statistical significance in age, respiratory frequency, systolic blood pressure, symptoms of dyspnea, previous chronic obstructive pulmonary disease, coronary heart disease history, white blood cells, neutrophils, lymphocytes, platelets, C-reactive protein, platelet counting, aspartate transaminase, albumin, total bilirubin, direct bilirubin, urea, estimated glomerular filtration rate, total cholesterol, low-density lipoprotein cholesterol, D-dimer, CD3+, CD4+, partial pressure of oxygen, partial pressure of CO2, blood oxygen saturation, other organ injury, clinical outcome and prognosis between patients with myocardial injury and without myocardial injury (all P<0.05). Multivariate logistic regression analysis showed that NLR was a risk factor for myocardial injury (OR=1.066，95%CI 1.021-1.111，P=0.033). ROC curve showed that NLR predicting AUC of myocardial injury in severe COVID-19 patients was 0.774 (95%CI 0.694-0.842), the optimal cut-off value of NLR was 5.768, with a sensitivity of 82.8%, and specificity of 69.5%. Conclusion: NLR may be used to predict myocardial injury in severe COVID-19 patients.

Establishment of a Rabbit Model of Chronic Obstructive Sleep Apnea and Application in Cardiovascular Consequences / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Although obstructive sleep apnea (OSA) has been recognized as a major risk factor for cardiovascular complications and its clinical features are well characterized, it is difficult to replicate the OSA hypoxic model in humans. We aimed to establish an experimental rabbit model for chronic OSA and to explore its application to measure blood pressure (BP), myocardial systolic function, and oxidative stress.</p><p><b>METHODS</b>The rabbit model for OSA was established by repeatedly closing the airway and then reopening it. A tube specially designed with a bag that could be alternately inflated and deflated according to a predetermined time schedule, resulting in recurrent airway occlusions and chronic intermittent hypoxia (CIH) imitating OSA patterns in humans, was used. Twenty-four rabbits were randomly divided into obstruction, sham, and control groups, and their upper airways were alternately closed for 15 s and then reopened for 105 s in a 120-s-long cycle, for 8 h each day over 12 consecutive weeks. Before and after the experiment, the BP of each rabbit was monitored. Levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in the serum, superoxide dismutase (SOD) activity, malondialdehyde (MDA) and reactive oxygen species (ROS) contents, as well as Na+-K+-ATPase/Ca2+-ATPase activities in cardiac muscle were examined. In addition, cardiac functional parameters were measured using echocardiography.</p><p><b>RESULTS</b>After 3 months, all rabbits in the obstruction group manifested sleepiness performance similar to that observed in OSA patients. Traces of airflow and SpO2showed that this model mimicked the respiratory events involved in OSA, including increased respiratory effort and decreased oxygen saturation. Gradually, the BP rose each month. CIH led to obvious oxidative stress and injured myocardial systolic performance. The serum levels of IL-6 and TNF-α increased significantly (64.75 ± 9.05 pg/ml vs. 147.00 ± 19.24 pg/ml and 59.38 ± 8.21 pg/ml vs. 264.75 ± 25.54 pg/ml, respectively, both P < 0.001). Compared with the sham and the control groups, myocardial activities of Na+-K+-ATPase/Ca2+-ATPase and SOD in the obstruction group decreased markedly, while ROS and MDA content increased.</p><p><b>CONCLUSIONS</b>These results show that the rabbit model for OSA simulates the pathophysiological characteristics of OSA in humans, which implies that this animal model is feasible and useful to study the mechanisms involved in the cardiovascular consequences of OSA.</p>

Anti-tumor activity of tanshinone IIA in combined with cyclophosphamide against Lewis mice with lung cancer

Objective To explore the anti-tumor activity of tanshinone IIA in combined with cyclophosphamide against Lewis mice with lung cancer and the effect on cellular immune function. Methods Lewis tumor cells were inoculated subcutaneously into the right armpit of mice in each group (n = 20) to establish Lewis lung cancer mice model. After model establishment, mice in the model group were given normal saline by lavage, qd. Mice in treatment I group were given intraperitoneal injection of Tan IIA, 15 mg/kg, qd. Mice in treatment II group were given intraperitoneal injection of CTX, 25 mg/kg, qd. Mice in treatment III group were given intraperitoneal injections of Tan IIA and CTX, in which the administration method of Tan IIA was the same as in treatment I group, continuously for 2 weeks, and the dosage of CTX was the same as in treatment II group, 24 h after model establishment, every other day. Mice were sacrificed 2 weeks after establishment. The tumor tissues were collected to calculate the anti-tumor rate. Immunohistochemistry was used to detect the expressions of Bcl-2, Bax, VEGF, Angiostatin, and Endostatin. FCM was used to detect T lymphocyte subsets in spleen and liver of mice. Results The tumor weight in treatment I, II, and III groups was significantly lower than that in the model group (P < 0.05). The tumor weight in treatment III group was significantly lower than that in treatment I and II groups (P < 0.05). The anti-tumor rate in treatment II and III groups was significantly higher than that in treatment I group (P < 0.05). Bcl-2 expression in the tumor tissues of treatment I, II, and III groups was significantly lower than that in the model group (P < 0.05), while Bax expression was significantly higher than that in the model group (P < 0.05). Bcl-2 expression in the tumor tissues of treatment I and II groups was significantly higher than that in treatment III group (P < 0.05), while Bax expression was significantly lower than that in treatment III group (P < 0.05). CD4

Anti-tumor activity of tanshinone IIA in combined with cyclophosphamide against Lewis mice with lung cancer

OBJECTIVE@#To explore the anti-tumor activity of tanshinone IIA in combined with cyclophosphamide against Lewis mice with lung cancer and the effect on cellular immune function.@*METHODS@#Lewis tumor cells were inoculated subcutaneously into the right armpit of mice in each group (n = 20) to establish Lewis lung cancer mice model. After model establishment, mice in the model group were given normal saline by lavage, qd. Mice in treatment I group were given intraperitoneal injection of Tan IIA, 15 mg/kg, qd. Mice in treatment II group were given intraperitoneal injection of CTX, 25 mg/kg, qd. Mice in treatment III group were given intraperitoneal injections of Tan IIA and CTX, in which the administration method of Tan IIA was the same as in treatment I group, continuously for 2 weeks, and the dosage of CTX was the same as in treatment II group, 24 h after model establishment, every other day. Mice were sacrificed 2 weeks after establishment. The tumor tissues were collected to calculate the anti-tumor rate. Immunohistochemistry was used to detect the expressions of Bcl-2, Bax, VEGF, Angiostatin, and Endostatin. FCM was used to detect T lymphocyte subsets in spleen and liver of mice.@*RESULTS@#The tumor weight in treatment I, II, and III groups was significantly lower than that in the model group (P  0.05). NK cell activity in treatment I, II, and III groups was significantly higher than that in the model group (P < 0.05). NK cell activity in treatment III group was significantly higher than that in treatment I and II groups (P < 0.05).@*CONCLUSIONS@#Tan IIA in combined with CTX can down regulate Bcl-2 expression in lung cancer tissues, up regulate Bax expression, inhibit the neovascularization of tumor tissues, and enhance the immunological function, with a significant anti-tumor activity.

Drawing up a Job Self-regulation Questionnaire for Airline Pilots / 航天医学与医学工程

Objective To draw up a job self-regulation questionnaire for airline pilots and to evaluate its reliabilities and validities.Methods A job self-regulation questionnaire was developed based on documents and interviews.In order to examine the validity,208 airline pilots of CAAC were tested and 31 department leaders of them were interviewed.Results The self-regulation of airline pilot was composed of eight key dimensions,which had been examined in the confirmatory factor analysis.The Cronbach of full questionnaire was ?=0.743,and the reliability of each dimension was beyond Cronbach ?=0.516.Coefficient of stability of the questionnaire was beyond 0.606(P