Objective To explore the characteristics of human thermal response in the natural cold environment.Methods Investigated and contrasted the skin temperature,thermal response characteristic and thermal comfort results of five women and fifteen men,aged 20 to 32 years,5 to 8 years of local living,in indoor warm environment and outdoor natural cold environment in the end of November,2007,in suburb of a city in Sinkiang(height 1 600 m,the lowest outdoor temperature in winter is-25℃ and the highest outdoor temperature in winter is 5℃,indoor average temperature is 18℃).The measurement on site and questionnaires were used.Results The mean thermal comfort vote(MTCV) mostly distributes around-3(mostly uncomfortable) when the outdoor temperature is-4.3--5.0 ℃,relative humidity is 65.2%-66.7%,The mean thermal sensation vote(MTSV) is-1.5(clod) to-3(quite cold).Human body could appear different degree of cold intensity sense and the body could not help quivering.Noses,ears and hands appeared different degree of rose color.Eyes became dryness and weep after staying long time outdoor.Conclusion Temperature,relative humidity and wind speed all around affected the mean thermal sense vote value and mean thermal comfort vote value.In the environment of low temperature,humidity and wind speed could increase the intension of cold action.Human is more sensitive to cold sense than thermal sense.

Objective To investigate the effect of pretreatment with dexmedetomidine alone or in combination with sufentanil on myocardial ischemia-reperfusion (I/R) injury in rats.Methods Fifty healthy male Sprague-Dawley rats,weighing 250-300 g,were anesthetized with intraperitoneal pentobarbital sodium 60 mg/kg.Myocardial I/R was induced by occlusion of anterior descending branch of left coronary artery for 30 min followed by 120 min of reperfusion.The rats were then randomly divided into 5 groups (n =10 each):sham operation group (group S),group I/R,dexmedetomidine pretreatment group (group DP),sufentanil pretreatment group (group SP),and dexmedetomidine + sufentanil pretreatment group (group DS).In group S the anterior descending branch was only exposed but not ligated.Dexmedetomidine 0.5μg/kg and sufentanil 0.1μg/kg were injected intraperitoneally 30 min before ischemia in groups DP and SP,respectively.Dexmedetomidine 0.5 μg/kg and sufentanil 0.1 μg/kg were injected intraperitoneally 30 min bbefore ischemia in group DS.Arterial blood samples were collected at 120 min of reperfusion for determination of serum creatine kinase (CK) and lactic dehydrogenase (LDH)concentrations.The rats were sacrificed at 120 min of reperfusion and hearts were removed for microscopic examination.Myocardial infarct size was calculated.The malondialdehyde (MDA) content and superoxide dismutase (SOD) activity in myocardial tissues were measured.Results Compared with group S,the serum CK and LDH concentrations were significantly increased,the myocardial infarct size was enlarged,and SOD activity was decreased in the other groups,MDA content was significantly increased in groups I/R,DP and SP (P ＜ 0.05 or 0.01).Compared with group I/R,the serum CK and LDH concentrations,MDA content and myocardial infarct size were significantly decreased,and SOD activity was increased in groups DP,SP and DS (P ＜ 0.05).Compared with group DS,the serum CK concentration was significantly increased,the myocardial infarct size was enlarged,and MDA content was increased in groups DP and SP,and LDH concentration was significantly increased and SOD activity was decreased in group DP (P ＜ 0.05).The pathological changes were significantly attenuated in groups DP and SP compared with group DS.Conclusion Dexmedetomidine pretreatment can reduce myocardial I/ R injury in rats,dexmedetomidine combined with sufentanil pretreatment provides better efficacy than either alone,and inhibition of lipid peroxidation is involved in the mechanism.

Objective To evaluate the effect of ulinastatin on oxidative stress injury to myocardial cells in diabetic rats in vitro.Methods The H9c2 cells were cultured in DMEM culture medium and the cells at the logarithmic growth phase were seeded in 96-well plates (density 1 × 104 cells/ml,200 μl/well) or in 6-well plates (density 1× 105 cells/m1,2 ml/well).The cells were randomly divided into 4 groups (n=18 each) using a random number table:normal control group (group C),high-glucose group (group HG),high-glucose + oxidative stress group (group HG+OS),ulinastatin +high-glucose+oxidative stress group (group U+HG+OS).The cells were cultured in high-glucose DMEM culture medium (25.0 mmol/L) for 48 h in group HG.After the cells were cultured in high-glucose DMEM culture medium for 24 h,H2O2 with the final concentration of 500 μmol/L was added to the high-glucose culture medium,and the cells were continuously cultured for 24 h in HG+OS and U+HG+OS groups.In group U+HG+OS,ulinastatin 400 U/ml was added to the high-glucose culture medium.The cells were collected for determination of cell viability,H9c2 apoptosis,activity of superoxide dismutase (SOD) and contents of malonadehyde (MDA).Apoptosis rate was calculated.The cell culture supernatant was collected for detection of lactate dehydrogenase (LDH) activity.Results Compared with group C,the cell viability and SOD activity were significantly decreased,and the apoptosis rate,MDA content and LDH activity were increased in the other groups.Compared with HG group,the cell viability and SOD activity were significantly decreased,and the apoptosis rate,MDA content and LDH activity were increased in HG+OS and U+HG+OS groups.Compared with group HG+OS,the cell viability and SOD activity were significantly increased,and the apoptosis rate,MDA content and LDH activity were decreased in group U + HG+ OS.Conclusion Ulinastatin can mitigate oxidative stress injury to myocardial cells in diabetic rats,and inhibited cell apoptosis is involved in the mechanism.

OBJECTIVE: To observe the effect of astaxanthin (ASTA) on the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) in suspended leukocyte-depleted red blood cells stored for transfusion. METHODS: The suspended leukocyte-depleted red blood cells were randomly divided into group A, B, C and D. The ASTA was added into preservation solution of suspended leukocyte-depleted red blood cells of group B, C and D with the final concentration 5, 10 and 20 μmol/L, respectively, while DMSO was added into cells of group A in the same volume. After 7, 14, 28 and 42 days of storage, the reactive oxygen species (ROS) content in red blood cells was detected by fluorescence microplate reader, malondialdehyde (MDA) content was detected by thiobarbituric acid (TBA) method, activity of SOD was detected by xanthine oxidase method, the activity of CAT was detected by visible light method, and activity of GSH-Px was detected by colorimetry. RESULTS: After 7, 14, 28 and 42 days of storage, the contents of ROS and MDA in suspended red blood cells of group B, C and D were significantly lower(P<0.05), while the activities of SOD and GSH-Px were higher than those of group A(P<0.05); and CAT activity in cells treated by ASTA was significantly higher at 28 and 42 days of storage in comparison with that of group A(P<0.05). There were positive correlations between the ROS, MDA content in suspended red blood cells of group A, B, C, D and storage time(P<0.01), while negative correlation between SOD, CAT, GSH-Px activity and storage time(P<0.01). CONCLUSION ASTA can decrease the oxidative stress level and peroxide damage degree by increasing the antioxidant enzyme activities in suspended leukocyte-depleted red blood cells during storage.
Antioxidants ; Catalase/metabolism* ; Erythrocytes ; Leukocytes ; Oxidative Stress ; Superoxide Dismutase/metabolism* ; Xanthophylls

Objective:To understand the problems existing in the curriculum design of food hygiene and nutrition for undergraduates, and put forward countermeasures to improve the quality of talents cultivation and promote professional development.Methods:Self-made questionnaires were distributed by convenience sampling method, through online and offline ways, and the graduates' opinions on the curriculum design of their school. Quantitative data were analyzed by SPSS 26.0, and qualitative data were analyzed by NVivo 11.0.Results:A total of 258 valid questionnaires were recovered, and the average score of graduates' satisfaction with teaching quality was 2.42±1.02. Graduates had different opinions on the importance of special courses, and 150 students (58.14%) were satisfied with major courses. Some graduates thought the time of special courses was unreasonable and there were few major courses. Besides, 141 graduates (54.65%) were satisfied with the clinical probation in their graduation colleges. Although graduates believed that innovation ability was important, innovative education courses were scarce at present.Conclusions:Graduates are less satisfied with the setting of undergraduate curriculum in food hygiene and nutrition. It is suggested to optimize professional courses setting, improve experimental facilities and equipment, strengthen the management of practice bases, and pay attention to the cultivation of students' innovation and entrepreneurship ability.

OBJECTIVETo explore the effect of astaxanthin (ASTA) on oxidative stress of intra- and extra- red blood cells during stored period and the protective function for cell membrane.

METHODSThe blood of volunteers was collected to prepare suspended red blood cells without leukocytes. Then the red blood cells were randomly divided into group A, group B, group C and group D. The ASTA was added into MAP preservation solution of group B, group C and group D, the final concentration of ASTA was 5, 10 and 20 µmol/L respectively. Group A was used as control group, in which only the dissolved liquid DMSO of ASTA was added. The red blood cells were stored in refrigerator at 2 °C-6 °C. On day 7, 14, 28 and day 42 of storage, the content of reactive oxygen species (ROS) in red blood cells was detected by fluorescence microplate reader. The content of malondialdehyde (MDA) was detected with TBA method. The content of hydrogen peroxide (H2O2) outside cell was detected with spectrophotometric method. The mean corpuscular volume(MCV) was detected with blood cell analyzer. The content of free hemoglobin(FHb) was detected with chemical colorimetry.

RESULTSThe ROS, MDA, FHb and H2O2 levels in B, C and D groups were lower than those in control group during the stored period. On day 7 and 14 of storage, among group B, group C, group D and group A, the MCV showed no difference in comparison with control group. On day 28 and 42 of storage, the MCV in B, C and D groups was lower than that in control group.

CONCLUSIONThe ASTA can reduce the oxidative stress level of stored red blood cells inside and outside, relieve the peroxidation damage of cell membrane.

Erythrocyte Count ; Erythrocytes ; Humans ; Hydrogen Peroxide ; Leukocytes ; Oxidative Stress ; Reactive Oxygen Species ; Xanthophylls