Objective To explore the effects of chronic stress and stress cessation on hypothalamic appetite regulators in mice,and to explore the stress-dependent mechanism of appetite change.Methods A total of 32 male C57BL/6 mice were randomly divided into control(Ctrl)group(n=16)and chronic unpredictable mild stress(CUMS)group(n=16).The mice in the CUMS group were given CUMS to establish the stress model,and those in the Ctrl group were fed normally.The food intake and weight of mice were recorded.The CUMS model was verified through tail suspension experiments and forced swimming experiments.Eight mice in the Ctrl group and 8 mice in the CUMS group were randomly sacrificed at the 12th week.The Ctrl group was re-grouped into the cessation-control(C-Ctrl)group(n=8),the CUMS group was re-grouped into the cessation-stress(C-CUMS)group(n=8),and the mice were sacrificed at the 15th week.The mRNA and protein levels of appetite-regulating factors,including orexin 1 receptor(OX1R),leptin receptor(LEPR)and agouti-related protein(AgRP)in the hypothalamus,were detected by quantitative polymerase chain reaction and immunochemistry.Results From week 2 to week 11 of stress,the food intake of the mice in the CUMS group was significantly higher than that in the Ctrl group(all P＜0.05),while there was no significant difference in body weight between the 2 groups within 11 weeks(all P＞0.05).Compared with the Ctrl group,the immobility durations of forced swimming and tail suspension of the CUMS group were markedly longer after 11 weeks(both P＜0.01),indicating successful modeling.AgRP and OX1R mRNA expression in the hypothalamus of the CUMS group was significantly increased(both P＜0.01),while LEPR mRNA expression was significantly decreased(P＜0.01);AgRP protein in the hypothalamic arcuate nucleus of the CUMS group was significantly higher than that of the Ctrl group(P＜0.05),and LEPR protein was markedly lower than that of the Ctrl group(P＜0.01).However,after 3 weeks of stress cessation,the C-CUMS group had less food intake and lower body weight than the C-Ctrl group(both P＜0.05).The LEPR mRNA of the C-CUMS group was significantly increased(P＜0.01),while AgRP and OX1R mRNA were not significantly different(both P＞0.05).There was no significant difference in AgRP protein levels between the C-CUMS group and the C-Ctrl group(P＞0.05),while LEPR protein level of the C-CUMS group was significantly higher than that of the C-Ctrl group(P＜0.01).Conclusion CUMS can lead to increased appetite in mice,which may involve the functional regulation of LEPR and AgRP.After the stress cessation,the appetite decreases,which may involve the functional regulation of LEPR.

Objective To investigate the changes in the levels of human blood nutritious metabolites and its major regulating factors after exposure to abnormal acceleration of sea state,and to provide clues for further investigating the mechanism of fatigue due to maritime operations.Methods Using randomly sampling method,60 healthy male adults from one troop were selected as the subjects on April 20,2010.All subjects were exposed to six degrees of freedom motion simulator ship for 15 min.Their blood samples were collected before and after exposure to abnormal acceleration immediately.The metabolomic technology was used to measure the levels of nutritious metabolites in the serum.Enzyme-linked immunosorbent assay or radioimmunoassay was used to measure the levels of glucocorticoids,adrenaline,insulin,glucagon,ghrelin,resistin,leptin,and gastric inhibitory peptide.Results After exposure to abnormal acceleration,the subjects showed significant decreases in the levels of serum essential amino acids,such as L-lysine [(23.63-±8.24)×106 vs (32.83±13.58)×106,P＜ 0.05],L-methionine[(4.16±1.12)×106 vs (5.80±1.69)×106,P＜0.05],and L-tryptophan[(29.38±8.56)×106 vs (35.93±11.82) ×106,P＜0.05],and the levels of some non-essential amino acids,such as L-histidine [(1.69± 0.55)×106vs (2.16±0.92)×106,P＜0.05] and 4-hydroxy-L-proline [(3.21±1.50)×106vs (7.92±4.79)×106,P＜ 0.05].After exposure to abnormal acceleration,the subjects had significant increases in the levels of serum carbohydrate metabolites,such as glucose [(2412.40±700.36) ×106 vs (1939.30±554.33) × 106,P＜0.05] and pyruvic acid [(9.97±5.96)×106 vs (2.43±1.34)×106,P＜0.05],and the levels of fat metabolites,such as β-hydroxybutyric acid [(37.47±60.21)×106 v.s (10.29±20.64)×106,P＜0.05],oleic acid [(31.94±30.39)×106 vs (15.94±10.37)×106,P＜0.05],and linoleic acid [(26.19±19.16)×106vs (13.58±6.29)×106,P＜0.05].After exposure to abnormal acceleration,the subjects had significant increases in the levels of serum glucocorticoids [(743.63±129.06) nmol/L vs (539.66±155.58) nmol/L,P＜0.05],adrenaline [(725.04±367.08) pmol/L vs (482.58±194.97) pmol/L,P＜0.05],glucagon [(5.85±1.57) pmol/L vs (5.18±1.64) pmol/L,P＜0.05],and ghrelin[(62.55±32.34) pmol/L vs (40.47±22.18) pmol/L,P＜0.05],and decreases in the levels of serum insulin [(107.41±21.09) pmol/L vs(150.89±48.65) pmol/L,P＜0.05],gastric inhibitory peptide[(41.05±17.91) pmol/L vs (170.34±82.64) pmol/L,P＜0.05],leptin [(25.62±21.75) nmol/L vs (46.50±27.40) nmol/L,P＜0.05],and resistin [(209.24±107.65) nmol/L vs (535.04±263.13) nmol/L,P＜0.05].Conclusion After exposure to abnormal acceleration of sea state,the levels of serum nutritious metabolites show significant changes and the levels of fatigue-associated products,such as serum pyruvic acid,increase significantly,which may be related to induced stress response and changes in the levels of metabolic regulators.

Objective To investigate the changes in the levels of human blood nutritious metabolites and its major regulating factors after exposure to abnormal acceleration of sea state,and to provide clues for further investigating the mechanism of fatigue due to maritime operations.Methods Using randomly sampling method,60 healthy male adults from one troop were selected as the subjects on April 20,2010.All subjects were exposed to six degrees of freedom motion simulator ship for 15 min.Their blood samples were collected before and after exposure to abnormal acceleration immediately.The metabolomic technology was used to measure the levels of nutritious metabolites in the serum.Enzyme-linked immunosorbent assay or radioimmunoassay was used to measure the levels of glucocorticoids,adrenaline,insulin,glucagon,ghrelin,resistin,leptin,and gastric inhibitory peptide.Results After exposure to abnormal acceleration,the subjects showed significant decreases in the levels of serum essential amino acids,such as L-lysine [(23.63-±8.24)×106 vs (32.83±13.58)×106,P＜ 0.05],L-methionine[(4.16±1.12)×106 vs (5.80±1.69)×106,P＜0.05],and L-tryptophan[(29.38±8.56)×106 vs (35.93±11.82) ×106,P＜0.05],and the levels of some non-essential amino acids,such as L-histidine [(1.69± 0.55)×106vs (2.16±0.92)×106,P＜0.05] and 4-hydroxy-L-proline [(3.21±1.50)×106vs (7.92±4.79)×106,P＜ 0.05].After exposure to abnormal acceleration,the subjects had significant increases in the levels of serum carbohydrate metabolites,such as glucose [(2412.40±700.36) ×106 vs (1939.30±554.33) × 106,P＜0.05] and pyruvic acid [(9.97±5.96)×106 vs (2.43±1.34)×106,P＜0.05],and the levels of fat metabolites,such as β-hydroxybutyric acid [(37.47±60.21)×106 v.s (10.29±20.64)×106,P＜0.05],oleic acid [(31.94±30.39)×106 vs (15.94±10.37)×106,P＜0.05],and linoleic acid [(26.19±19.16)×106vs (13.58±6.29)×106,P＜0.05].After exposure to abnormal acceleration,the subjects had significant increases in the levels of serum glucocorticoids [(743.63±129.06) nmol/L vs (539.66±155.58) nmol/L,P＜0.05],adrenaline [(725.04±367.08) pmol/L vs (482.58±194.97) pmol/L,P＜0.05],glucagon [(5.85±1.57) pmol/L vs (5.18±1.64) pmol/L,P＜0.05],and ghrelin[(62.55±32.34) pmol/L vs (40.47±22.18) pmol/L,P＜0.05],and decreases in the levels of serum insulin [(107.41±21.09) pmol/L vs(150.89±48.65) pmol/L,P＜0.05],gastric inhibitory peptide[(41.05±17.91) pmol/L vs (170.34±82.64) pmol/L,P＜0.05],leptin [(25.62±21.75) nmol/L vs (46.50±27.40) nmol/L,P＜0.05],and resistin [(209.24±107.65) nmol/L vs (535.04±263.13) nmol/L,P＜0.05].Conclusion After exposure to abnormal acceleration of sea state,the levels of serum nutritious metabolites show significant changes and the levels of fatigue-associated products,such as serum pyruvic acid,increase significantly,which may be related to induced stress response and changes in the levels of metabolic regulators.

Objective To analyze and evaluate the fatigue status of the ship crew , as well as the air quality of the ship cab-ins, and to find out influencing factors for the fatigue among the ship crew , so as to provide theoretical evidence and guidance for the maintenance and improvement of the health of the ship crew during prolonged deployment at sea .Methods Investigation and analysis on the fatigue status among the ship crew both before and after deployment were made by using the questionnaire of 《the Subjective Fa-tigue Symptom Checklist》.Air quality of the ship cabins was analyzed by using Gasmet DX 4035 FT-IR multi-component air analyzer and assessed in accordance with Indoor Air Quality Standards .Results (1) One week after deployment , fatigue symptoms in all the shipboard personnel deteriorated significantly , and three fatigue factors including "somatic", "mental"and "neurosensory"factors were all considerably increased .(2) The levels of formaldehyde and SO 2 in some cabins exceeded the permissible limits .Conclusion The fatigue status among the ship crew after deployment at sea obviously deteriorated , as compared with that before deployment .The levels of harmful gases in some cabins exceeded the limits as specified in the standards , which could worsen the fatigue status among the ship crew.

Objective: To investigate the relationships between constitutional types of traditional Chinese medicine (TCM) and motion sickness. Methods: A survey of TCM constitutions in ocean sailors participating in a voyage was performed by using the TCM Constitution Questionnaire developed by Beijing University of Traditional Chinese Medicine, while the survey of motion sickness was operated by Graybiel's diagnostic criteria. The incidences of motion sickness among sailors with different types of constitutions were compared. Results: Prior to the voyage, 50.3% of sailors exhibited a gentleness constitution, 14.5% were of dampness-heat constitution, 10.3% were of qi-stagnation constitution, whereas the percentages of qi-deficiency, yang-deficiency, yin-deficiency, blood-stasis and special diathesis constitutions were 6.2%, 7.6%, 6.2%, 4.1% and 0.7%, respectively. None exhibited a phlegm-dampness constitution. By the end of the 176-day voyage, the percentages of gentleness, dampness-heat, qi-depression, qi-deficiency, yang-deficiency, yin-deficiency, blood-stasis, special diathesis and phlegm-dampness constitutions were 33.8%, 13.8%, 13.1%, 11.0%, 6.9%, 9.7%, 4.1%, 0.7% and 6.9%, respectively. The incidence of motion sickness was 69.7% (101 sailors) during this voyage. The incidences of motion sickness among sailors with different types of constitutions before the voyage showed significant difference (P<0.001). The incidence of motion sickness was higher in the sailors with dampness-heat constitution than in those with gentleness constitution. Conclusion: Types of Chinese medical constitution can be related to susceptibility to motion sickness. Furthermore, ocean voyage may have an effect or influence on the type of Chinese medical constitution of sailors involved.

Objective: To investigate the antimotion sickness effects of ginsenosides combined with dexamethasone in rats. Methods: Fifty SD rats were randomly divided into 5 groups: normal saline, scopolamine-treated, ginsenosides-treated, dexamethasone-treated and ginsenosides plus dexamethasone-treated groups. There were 10 rats in each group. The rats in each group were fed with corresponding ingredients respectively, and then the rats were exposed to abnormal acceleration for one hour. The motion sickness index, the level of kaolin consumption and the course and time of spontaneous activity were observed. Results: The motion sickness index and the level of kaolin consumption of acceleration-exposed rats in ginsenosides plus dexamethasone-treated group were significantly lower than those in normal saline group. And the course and time of spontaneous activity of acceleration-exposed rats in ginsenosides plus dexamethasone-treated group were significantly higher than those in normal saline group. The level of body weight increment of acceleration-exposed rats in ginsenosides plus dexamethasone-treated group was significantly higher than that in dexamethasone-treated group. Conclusion: Ginsenosides combined with dexamethasone can significantly increase tolerance to acceleration of rats, and the drug combination can decrease side effects of methylprednisolone, such as body weight loss.