TNF-α induced RIP1-dependent apoptosis in L929-A cells by interrupting mitochondrial respiratory chain complex Ⅲ / 军事医学

Objective To explore the mechanism by which tumor necrosis factor alpha(TNF-α) induces RIP1 kinase-dependented apoptosis in L929-A fibroblastoma cells.Methods The sub-mitochondrial localization of receptor-interacting protein 1(RIP1),caspase-8 and Bid proteins was detected by dose-gradient trypsin digestion and Western blotting.The levels of reactive oxygen species (ROS),intracellular calcium concentration,mitochondrial membrane potential (MMP),and cellular adenosine triphosphate(ATP) content were determined by fluorescent probe labeling and flow cytometry assay.The mitochondrial respiratory chain complex Ⅰ and Ⅲ activities were detected by commercial kits.Nec-1,A RIP1 kinase specific inhibitor,and RIP1-/-or Bid-/-L929-A cells were used to detect the roles of RIP1 kinase and Bid protein in cell death.Results RIP1,caspase-8 and Bid proteins were co-located in the outer membrane of mitochondrial.TNF-α exposure for 3 h could induce Bid cleavage,inhibit mitochondrial respiratory chain complex Ⅲ activity and reduce MMP.Following these changes and after TNF-α exposure for 6-12 h,the intracellular calcium concentration and ROS were increased,whereas the ATP concentration was decreased,and the cells were killed.Inhibiting RIP1 kinase or knockdown RIP1 or Bid protein could suppress all the cytotoxic effects of TNF-α.Conclusion TNF-α treatment can result in RIP1 kinase-mediated Bid cleavage and inhibit mitochondrial respiratory chains and cell energy metabolism,which ultimately leads to the death of L929-A cells.

Identification of role of PI3K in mediating necroptosis of L929 cells induced by tumor necrosis factor alpha / 军事医学

Objective To identify the role of phosphatidylinositol-3-kinase(PI3K) in mediating necroptosis induced by tumor necrosis factor alpha (TNFα) and the involved mechanism.Methods Knockdown of p110α,receptor-interacting protein 1(RIP1) or both p110αand RIP1 was mediated by the specific short hairpin RNA (shRNA) lentivirus and verified by RT-PCR or Western blotting .In addition , Western blotting was used to detect phosphorylation of mixed lineage kinase domain-like protein(MLKL) and protein kinase B(AKT) or tetramerization of MLKL.Cell death was measured by micros-copy and flow cytometry.Results AKT phosphorylation and TNFα-induced necroptosis of L929 cells were suppressed by the inhibitors of PI3K or AKT, as well as p110αknockdown.Moreover, RIP1 knockdown did not inhibit L929 cell death induced by TNFαplus Z-VAD, but the RIP1-independent necroptosis was inhibited by p 110αknockdown.In addition, p110αknockdown suppressed MLKL phosphorylation and tetramerization induced by TNFαwith Z-VAD in L929 cells. Conclusion PI3K mediates necroptosis of L929 cells induced by TNFαby activating AKT and MLKL, respectively.

Effect of military performance stress on sympathetic adrenal medulla in submariners / 军事医学

Objective To evaluate the effect of military performance stress on the changes of concentrations in salivary chromogranin A ( CgA) ,β-endorphin (β-EP) and salivary IgA ( sIgA) of submariners.Methods Twenty-nine submarine soldiers were selected, and their saliva samples were collected separately at the end of a long dive trip and nine months after relaxation ashore.In addition,the saliva samples of twenty-eight graduate students were collected as the normal control.The method of ELISA was used to detect the level of salivary CgA,β-EP and sIgA.Results After long-term dive training, the submariners showed significantly decreased CgA,β-EP and sIgA.Conclusion After a long term dive trip, chronic military performance stress is associated with the decline of salivary CgA,β-EP and sIgA, indicating that the function of sympathet-ic adrenal medulla is suppressed.The biological significance of these changes needs to be assessed in the future.

ANALYSIS ON THE RESPONSIBILITY OF GOVERNMENT FROM OUTCOMES EVALUA-TION OF DRUG PRICE ADDITION CANCELING POLICY ON INCOMES IN DONGGUAN'S PUBLIC HOSPITAL / 现代医院

Objective To analyze on the responsibility of government for drug price addition canceling policy on incomes . Methods We Collected the 3-A hospital financial information statements and drug use data from January 2013 to September 2013 ( before reform) and from October 2013 to June 2014 ( after reform) .Results After taking evaluation of drug price addition cance-ling policy on incomes in the hospital, outpatient visits grew 9.62%, discharges increases 3.50%, and the outpatient average com-pensation fell by 4.69% and hospitalization fees per person increase 3.58%.Conclusion Preliminary results were obtained in con-trolling health care costs, medical services in ascension.The government's economic compensation economic compensation is difficult to make up for the cancellation of drug addition and reduce the reasonable income .It is suggested that we should improve the compen-sation scheme and assessment standards, and further strengthen the hospital internal management.

Evaluation of performance stress among military submarine soldiers by using salivary cortisol,DHEA-S and cortisol/DHEA-S ratio assay / 军事医学

Objective To investigate the significance of salivary cortisol , dehydroepiandrosterone sulfate (DHEA-S) and cortisol/DHEA-S ratio changes for evaluation of military performance stress .Methods Forty submarine soldiers were selected, whose saliva samples were collected separately at the end of long-term dive training and after nine months of relaxation break.In addition, the saliva samples of thirty-four graduate students were collected the moment they finished a three-hour final examination and one week later .The method of ELISA was used to detect the levels of salivary cortisol and DHEA-S and to count their ratio .Results After long-term dive training , the submarine soldiers showed significantly decreased DHEA-S and an increased cortisol/DHEA-S ratio, but the cortisol level did not change very much .In contrast, the final examination stress did not change the level of cortisol , DHEA-S or the cortisol/DHEA-S ratio among these students.Conclusion This is the first study to show that long-term, chronic military performance stress is associated with the salivary DHEA-S and cortisol/DHEA-S ratio changes .The increase in the cortisol/DHEA-S ratio may be used as an important and useful biomarker to evaluate chronic stress .In addition , it is relatively simple and sensitive to detect stress biomarkers by using saliva samples .

Effect of acute high altitude exposure on lung functions and relationship between lung function and AMS / 军事医学

Objective To investigate the effect of acute high altitude exposure on lung functions and the relationship between lung functions and acute mountain sickness ( AMS) .Method We collected the lung function and Lewis Lake data of 73 subjects (aged 18 to 26,male) at 400 m above sea-leve and those at high altitude(exposure to 3900 m, 5 d).Results Compared with sea-level, lung functions decreased in forced vital capucity (FVC), maximum midexpiratory flow(MMF), V50, V25 while forced expiratory volume in 1 second(FEV1), peak expiratory flow(PEF), V75 did not change.FVC, FEV1, PEF, MMF were used to analyze the relationship between lung functions and AMS .There was no difference in lung functions between AMS group and NON AMS group at sea-level, but lung functions of AMS group were significantly lower than those of NON AMS group in FVC , MMF at high altitude .There was difference between AMS group and NON AMS group in the rate of change of FVC and MMF .Logistic regression analysis showed that the rate of change of FVC was an independent risk factor , while correlation analysis showed that the change of FVC and the change of oxygen saturation were relevant.Conclusion Lung functions showed restrictive decrease after acute high altitude exposure .Changes of lung func-tions will increase hypoxia and susceptiblity to AMS .

Effects of five kilometers walking at 3200 m high altitude on acute mountain sickness / 重庆医学

Objective To evaluate the effect of moderate activities at moderate high altitude on acute mountain sickness (AMS) incidence .Methods Ninety-one healthy sea level residents traveled from sea level (345 m) to high altitude city (3200 m) ,by train within 48-hour .They walked 5 kilometers after 2-night stayed ,Lake Louis Score (LLS) Questionnaires ,blood pressure(BP) and oxygen saturation (SpO2 ) was administered before and after walking .Results Seven subjects were excluded because of incomplete data .The incidence of AMS before and after exercise was 20 .24% (n=17/84) and 11 .90% (n=10/84) respectively(P>0 .05) .Af-ter a 5 kilometer walking ,the heart rate increased from (73 .83 ± 9 .96)bpm to(84 .31 ± 12 .55)bpm (P<0 .05) ,Systolic BP and SpO2 level decreased from(128 .86 ± 13 .93)mm Hg to (124 .48 ± 13 .13)mm Hg ,(92 .80 ± 2 .25)% to (89 .94 ± 2 .45)% (P<0 .05) .Headache symptom improved after walking (P<0 .05) .Smoking was negative correlate with LLS score before and after ex-ercise(P<0 .05) .There is no relation between SpO2 and LLS scores .Conclusion Walking five kilometers at 3200 m improve head-ache symptom and tend to decrease AMS .