Objective Acute lung injury induced by variety causes can be reduced by mesenchymal stem cells.Some studies have shown that mesenchymal stem cell-derived exosomes have similar features with mesenchymal stem cell,but its role in acute lung injury is less studied.The study was to investigate the protective role and underlying mechanisms of bone marrow mesenchymal stem cell-derived exosomes (BMSC-DEs) on smoke inhalation injury (SⅡ) in rats.Methods Thirty Wistar rats were randomly divided into 3 equal groups:normal control group,smoke inhalation injury (SⅡ) model group and bone marrow mesenchymal stem cell-derived exosomes (BMSC-DEs) treated group.12 h after establishing the SⅡ model,BMSC-DEs treated group was injected with 0.5 mL BMSC-DEs (derived from 4× 106 BMSCs),and normal control group and SⅡ model group were injected with equivalent volume of normal saline.7 days later,samples were collected.The histopathologic changes of lung were observed after HE staining;BCA was used to test the amounts of total protein in bronchoalveolar lavage fluid (BALF);Enzyme linked immunosorbent assay was used to test the levels of tumor necrosis factor-α (TNF-α) and keratinocyte growth factor (KGF) in the lung tissue;Immunohistochemical was used to test the levels of pulmonary surfactant protein C(SP-C).Results The BALF levels of total protein of SⅡ group was significantly higher than those of normal control group (P＜0.01) and BMSC-DEs groups(P＜0.05);Compared with normal group [(0.164±0.021) ng/L],the levels of tumor necrosis factor-α of SII and BMSC-DEs groups [(0.355±0.106)、(0.234±0.024) ng/L] (P＜ 0.05) were significantly higher,and SⅡ group was higher than that of BMSC-DEs group(P＜0.01);Compared with normal group,the KGF protein expression level in lung tissue of SⅡ group was significantly lower (P＜0.05),but BMSC-DEs group was higher (P＜0.05).BMSC-DEs group was higher than SⅡ group (P＜0.01);Immunohistochemistry showed that the SP-C expression level in lung tissue of SⅡ group was significantly lower than those of other groups (P＜0.05).There was no statistically difference between BMSC-DEs group and control group (P＞0.05).Conclusion BMSC-DEs has a protective effect of smoke inhalation injury rats,the underlying mechanism may be related to BMSC-DEs to reduce inflammation and promote restoration of the alveolar epithelial type Ⅱ.

Objective To investigate changes in the nental health status of the ship crew onboard surface naval vessels during a prolonged deployment, so as to provide scientific basis for the development of sound psychological health service measures for the ship crew. Methods Reproducibility and cross - sectional survey were conducted to investigate the emotional status of the ship crew aboard a certain naval surface vessel with symptom check list (SCL-90), 7 days before deployment, and on the 77th, 142nd, and 204th days after deployment during a prolonged ocean - going voyage. The obtained data were compared with the norms of the Chinese servicemen. Results The mental health status of the ship crew was on the whole in good mode before deployment. Total average score and various SCL-90 patterns were obviously lower than the norms of the Chinese servicemen(P＜0. 05 ). On the 77th day after deployment, the psychological state of the ship crew degraded markedly, manifested by the elevation of the SCL-90 total mean score and other scores, such as somatizaion, hostility, crankiness and other factors, when compared with those after deployment( P ＜0. 05 ).Of all the scores, the scores of hostility and crankiness were significantly higher than the norms of the Chinese servicemen( P ＜0. 01 ). Total SCL-90 average score and various factor scores on the 142nd and 204th days after deployment dropped sharply, except that one other factor score of SCL-90 was higher than that before deployment(P ＜0. 01 ). Screening positive rate of SCL-90 indicated that positive rates on the 77th( 15. 1% )and 204th days ( 20% ) were all obviously higher than that of pre - deployment( 2. 4% ) ( P ＜ 0. 01 ). However,no statistical differences could be seen in the scores on 142nd day(7.7% ), when compared with that of predeployment(2. 4% ) ( P ＞ 0. 05 ). Conclusions The psychological status of the ship crew, on the whole,degraded markedly during the initial stage of a prolonged deployment, then, would gradually come to normal with adaptation thereafter. Nevertheless, individual psychological status showed a tendency of obvious differentiation in the late stage of deployment.

Objective To investigate changes in the nental health status of the ship crew onboard surface naval vessels during a prolonged deployment, so as to provide scientific basis for the development of sound psychological health service measures for the ship crew. Methods Reproducibility and cross - sectional survey were conducted to investigate the emotional status of the ship crew aboard a certain naval surface vessel with symptom check list (SCL-90), 7 days before deployment, and on the 77th, 142nd, and 204th days after deployment during a prolonged ocean - going voyage. The obtained data were compared with the norms of the Chinese servicemen. Results The mental health status of the ship crew was on the whole in good mode before deployment. Total average score and various SCL-90 patterns were obviously lower than the norms of the Chinese servicemen(P＜0. 05 ). On the 77th day after deployment, the psychological state of the ship crew degraded markedly, manifested by the elevation of the SCL-90 total mean score and other scores, such as somatizaion, hostility, crankiness and other factors, when compared with those after deployment( P ＜0. 05 ).Of all the scores, the scores of hostility and crankiness were significantly higher than the norms of the Chinese servicemen( P ＜0. 01 ). Total SCL-90 average score and various factor scores on the 142nd and 204th days after deployment dropped sharply, except that one other factor score of SCL-90 was higher than that before deployment(P ＜0. 01 ). Screening positive rate of SCL-90 indicated that positive rates on the 77th( 15. 1% )and 204th days ( 20% ) were all obviously higher than that of pre - deployment( 2. 4% ) ( P ＜ 0. 01 ). However,no statistical differences could be seen in the scores on 142nd day(7.7% ), when compared with that of predeployment(2. 4% ) ( P ＞ 0. 05 ). Conclusions The psychological status of the ship crew, on the whole,degraded markedly during the initial stage of a prolonged deployment, then, would gradually come to normal with adaptation thereafter. Nevertheless, individual psychological status showed a tendency of obvious differentiation in the late stage of deployment.