The prevention of myocardial and brain dysfunction induced by positive acceleration (+Gz) exposure is the focus in the field of aerospace medicine research topic .The characteristics and mechanisms that +Gz exposure caused damages to vital organs such as heart and brain remain to be further elucidated .The research literature about +Gz acceleration exposure-induced heart and brain injuries in experimental animals and its mechanisms at home and abroad was reviewed in this paper .

Objective To study the effect of rhodiola crenulata compound on serum corticosterone and myocardial glucocorticoid receptor ( GR) in rats exposed high sustained +Gz.Methods Seventy-two healthy SD rats were randomly divided into six groups: blank control group, stress control group, +10 Gz stress group and low, medium, high dose drug group, with twelve rats in each.20 mL/kg menstruum was fed to each rat once per day for 14 days.Low, medium and high dose drug group were fed with rhodiola crenulata compound at doses of 0.75 g/kg, 1.5 g/kg and 3.0 g/kg respectively, the other three groups were fed with equal volume saline.Rats were exposed to high +Gz in 15th day.The concentration of corticosterone in the serum of each group rats was detected with ELISA. Western blot was used to detect the expressions of GR in the myocardium of each group rats .Results The content of corticosterone was significantly elevated in +10Gz stress group, while the expression of GR in the myocardium was markedly declined (P <0.01,P <0.05).However, compound preconditioning could decrease concentration of corticosterone in the serum and enhance the expression of GR in the myocardium from rats after +10 Gz exposure. The corticosterone concentration of medium and high dose drug groups was significantly lower and the level of GR expression in the myocardium was significantly higher than that of +10 Gz stress group ( P <0.05 , P <0.01 ) . Conclusion Rhodiola crenulata compound preconditioning could regulate the concentration of corticosterone in the serum and the level of GR expression in the myocardium of the rats exposed +10 Gz, which may be related with its protective effect on high sustained +Gz-induced injury of myocardium.

Objectives: To observe the roles of nuclear factor ?B(NF ?B) in corticosterone injured hippocampal neurons. Methods:Two groups of primary hippocampal neurons were cultured for 8～10 days. One group was treated with 1?10 -5 mol/L corticosterone. The total cellular nuclear protein levels were extracted at 0.5,1,2 and 4 hours, respectively. Electrophoresis mobility shift assay (EMSA) was used to detect the expression of NF ?B activation. Another group was treated with ?B decoy DNA(25 ?mol/L) to inhibit the activity of NF ?B for 2 hours before 1?10 -5 mol/L corticosterone was intervened. MTT was used to observe the effects of corticosterone induced neurons injury after 6,12,24 and 48 hours. Results:The activity of NF ?B became significantly lower than that in the control group after corticosterone acted on neurons for 1 hour. As time went on, its effects became more conspicuously. The injury of hippocampal neurons aggravated when the activity of NF ?B was inhibited by ?B decoy DNA. Conclusions: NF ?B plays a protective role in corticosterone induced hippocampal neuron injury.

Objective:To evaluate the predictive value of sequential organ failure assessment (SOFA) for 28-day mortality in patients with post-cardiac arrest syndrome (PCAS).Methods:Retrospective analysis of 125 patients with PCAS who were treated in Emergency Intensive Care Unit (EICU) of Wenzhou People's Hospital from July 2016 to July 2021. Clinical data were collected, including age, gender, underlying diseases, acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ), SOFA score on admission to EICU and 28-day mortality. Univariate and multivariate Logistic regression model was constructed to analyze the influencing factors of PCAS patients, which was used to examine the independent correlation between SOFA score and 28-day mortality. Receiver operator characteristic curve (ROC curve) was used to determine the best predictive value of SOFA score and 28-day mortality in PCAS patients.Results:Among the 125 PCAS patients, there were 91 males and 34 females with an average age of (58.7±15.1) years old, and 97 died and 28 survived within 28 days. The overall SOFA score ranged from 7 to 15 points, with an average of 10.9 (10.0, 12.0) points. The SOFA score of non-survival group was significantly higher than that of the survival group [points: 11.0 (10.0, 12.0) vs. 9.5 (9.0, 10.0), P < 0.05]. This difference between SOFA score mainly caused by the neurological and cardiovascular systems. After excluding neurological factors, the SOFA score of the non-survival group was still significantly higher than that of the survival group [points: 8.0 (6.0, 8.0) vs. 6.5 (6.0, 7.0), P < 0.05]. SOFA score was found to be an independent risk factor for 28-day mortality in PCAS patients by multifactorial Logistic regression analysis [odds ratio ( OR) = 1.97, 95% confidence interval (95% CI) was 1.24-3.04]. The correlation between neurological score and mortality was the highest in subgroups ( OR = 3.47, 95% CI was 1.04-11.52). The area under the ROC curve (AUC) predicted by SOFA score was 0.81 (95% CI was 0.73-0.89). When SOFA score cut-off value was 10.5 points (10 or 11 points), the sensitivity and specificity of SOFA score for predicting 28-day mortality in patients with PCAS were 67.0% and 82.1%, respectively. Conclusions:The SOFA score is quite accurate in predicting 28-day mortality in patients with PCAS.