Objective To analyze the variation and influencing factors of distant vision of students during the recruitment selection and medical examination in two Air Force youth aviation schools in Northeast China in order to protect the youth aviation school students against myopia and to provide reference for interventions.Methods The distant vision of students of each grade in two schools in Northeast China was observed during the recruitment selection and during 2017 medical examination,and was statistically analyzed.The influencing factors of vision were investigated and analyzed.Results There was no statistically significant difference in the distant vision constituent ratio of students in Grade One and Grade Two during the recruitment selection and 2017 medical examination (P ≥ 0.05),but the difference was statistically significant in the distant vision constituent ratio of students in Grade Three during the recruitment selection and 2017 medical examination(P ＜0.01).There was statistically significant difference in the paired variable differences of students in each grade(P ＜0.01).The Logistic analysis result showed that reading distance and eating fruits and vegetables were the two important factors that influenced the visual acuity of the students.Conclustion The distant vision gets worse in the second semester of Grade Two,and the range of visual fluctuation is large.So regular examinations of visual acuity should be conducted and feasible measures of myopia protection should be taken to preserve hight-qnality sources of students.

Aviation ; Humans ; Physical Fitness ; Resistance Training ; Schools ; Students

BACKGROUNDMolecular hydrogen, as a novel antioxidant, has been proven effective in treating many diseases. This study aimed to evaluate the therapeutic effects of hydrogen saturated saline in treatment of a rat model of diabetes mellitus and a rat model of insulin resistant.

METHODSA rat diabetes mellitus model was established by feeding a high fat/high carbohydrate diet followed by injection of a small dose of streptozotocin, and an insulin resistant model was induced with a high glucose and high fat diet. Hydrogen saturated saline was administered to rats with both models conditions on a daily basis for eight weeks. A pioglitazone-treated group and normal saline-treated group served as positive and negative controls. The general condition, body weight, blood glucose, blood lipids, and serum insulin levels of rats were examined at the 8th week after treatment. The oxidative stress indices, including serum superoxide dismutase (SOD), glutathione (GSH) and malondialdehyde (MDA) were also evaluated after eight weeks of treatment using the commercial kits.

RESULTSHydrogen saturated saline showed great efficiency in improving the insulin sensitivity and lowering blood glucose and lipids. Meanwhile, the therapeutic effects of hydrogen saturated saline were superior to those of pioglitazone. Hydrogen saturated saline markedly attenuated the MDA level and elevated the levels of antioxidants SOD and GSH.

CONCLUSIONHydrogen saturated saline may improve the insulin resistance and alleviate the symptoms of diabetes mellitus by reducing the oxidative stress and enhancing the anti-oxidant system.

Animals ; Diabetes Mellitus, Experimental ; drug therapy ; Hydrogen ; therapeutic use ; Hypoglycemic Agents ; therapeutic use ; Insulin Resistance ; Oxidative Stress ; drug effects ; Rats ; Sodium Chloride ; chemistry ; Thiazolidinediones ; therapeutic use

Objective To investigate and analyze the changes in visual acuity,refractive condition and related influencing factors among the teenager aviation school students in order to ensure the effectiveness of vision surveillance.Methods Four hundred and three students of teenager aviation schools were selected as subjects.The data of their visual changes and refractive condition during the school selection examination and three months after the examination was compared and investigated by questionnaires.The statistics were processed using Wilcoxon's sign rank test and Logistic regression analysis.Results The visual acuity changes were significant (P ＜ 0.05) after only three months at school.The hypopsia rate was 28.79％,and the vision of 9.68％ of the students dropped below 0.8.After mydriasis,the results showed that 27.05％ of the students had refractive errors.Reading posture and food preferences were the two important factors that influenced the visual acuity of the students with short-term vision loss.Conclusion It is important to monitor the vision and refraction regularly to reduce the waste of resources,optimize the selection of potential pilots and develop visual protection measures.Continuous protection,and good visual habits will really help to protect students' vision.

Objective To optimize the nasal examination procedures for preliminary medical selection of pilot cadets,to reduce the use of medicine for nasal congestion,to simplify the workflow and to improve the efficiency.Methods In the course of recruiting pilots,all the 306 candidates in seven districts of a province were selected and randomly divided into the exercise-first group (n =166) and the spraying-first group (n =140).In the exercise-first group,the nasal cavity of the students was observed under the anterior rhinoscope at three time points:before exercise/spraying,after simple exercise,and after exercise/spraying(exercise first).In the second group,the nasal cavity was observed under the anterior rhinoscope at three time points:before exercise/spraying,after simple spraying,and after exercise/spraying(spraying first).Conclusions were drawn after nasal examination,and the percentage of clear conclusions in each group was statistically analyzed.Results In the case of simple exercise or simple nasal spraying,clear conclusions could be drawn about most of the candidates.There was no significant difference between the simple nasal spraying group and simple exercise group in the rate of clear conclusions.Conclusion During the preliminary recruitment of pilot students,the exercise method can be used to shrink the nasal cavity.For a few candidates whose conclusions cannot be drawn after exercise,nasal spray can be added to reduce congestion improve efficiency,and reduce the use of nasal congestion,thus reducing the indireet damage to candidates.During the re-check and final check,the nasal spray agent can be used to reduce the congestion and at the same time fast squatting 50 times in two minutes can be used as a the nasal cavity contraction method.

OBJECTIVE: To investigate the effect of oxidative stress on the accumulation of heat shock protein 70 (HSP70) within C2C12 myogenic cells. METHODS: Heat shock response (42 degrees C for 1 h and recovery for 12 h at 37 degrees C) was used to induce the expression of heat shock protein 70. We constructed a recombinant plasmid of HSP70 with enhanced green fluorescent protein (EGFP). After being transfected transiently into C2C12 cells, immunoblotting was used to detect the expression of HSP70 induced by heat shock response and transfection. Immunocytochemistry, fluorescent microscopy and immunoblotting were used to detect the translocation of HSP70. RESULTS: Immunoblotting showed that the overexpression of HSP70 was induced by heat shock response and transient transfenction. HSP70 localized within the cytoplasm of the normal cells, but HSP70 translocated from the cytoplasm to the nucleus and the nucleolus at 1 h after the treatment of oxidative stress (0.5 mmol/L H2O2) by using immunocytochemistry, fluorescent microscopy and immunoblotting for cellular partial proteins. CONCLUSION Oxidative stress may induce the accumulation of heat shock protein 70 within the nucleolus.
Cell Nucleolus ; metabolism ; Cells, Cultured ; HSP70 Heat-Shock Proteins ; metabolism ; Humans ; Myoblasts ; cytology ; metabolism ; Myocytes, Cardiac ; cytology ; metabolism ; Oxidative Stress ; physiology

OBJECTIVETo investigate the inhibitory effect of salidroside (Sal) on pulmonary microvascular endothelial cell (HPMEC) apoptosis induced by simulated microgravity and its mechanism.

METHODSHuman pulmonary microvascular endothelial cells cultured in vitro were divided into control group, clinorotation group and clinorotation+Sal pretreatment groups. Microgravity was simulated by clinorotation. The apoptotic rate of HPMECs was detected by flow cytometry using Annexin V-FITC staining, and the expressions of bcl-2, bax, and caspase-3 at the mRNA and protein levels were determined by real-time PCR and Western blotting, respectively.

RESULTSA 72-h clinorotation significantly induced apoptosis in HPMECs. Real-time PCR results demonstrated a significantly lowered bcl-2 but increased bax and caspase-3 mRNA expressions in clinorotation group as compared with those in the control group. Western blotting showed that clinorotation inhibited the protein expressions of PI3K and p-AKT and increased caspase-3 protein expression. Salidroside significantly inhibited the cell apoptosis, reversed the expressions of Bcl-2 and Bax, and attenuated the decrease in the protein expression of PI3K and phosphorylation level of AKT. Salidroside also antagonized the activation of caspase-3.

CONCLUSIONPI3K/AKT pathway and caspase 3 are involved in the apoptosis of HPMVECs induced by clinorotation, and the effect of clinorotation can be reversed by salidroside, suggesting the potential value of salidroside for application in spaceflight.

Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Cell Line ; Endothelial Cells ; cytology ; drug effects ; metabolism ; Endothelium, Vascular ; cytology ; drug effects ; Glucosides ; pharmacology ; Humans ; Lung ; blood supply ; Phenols ; pharmacology ; Signal Transduction ; Weightlessness

Objective To improve the load resistance ability of students in teenager aviation schools and carry out specialized training for the body situation and shape of students.Methods We selected students from 14 teenager aviation schools and measured their height,weight,and the circumferences of necks,chests,upper-arms,waists,hips,and thighs.We compared the data of these students from different areas and the parameters were analyzed statistically by correlation analysis.Results Totally 411 students from 6 southern schools and 403 students from northern schools were investigated.Their average body height,weight and body mass index (BMI) were (172.3 ± 4.39) cm,(62.7 ± 7.3) kg,and (21.1 ± 2.23)kg/m2 respectirely.Students from northern schools were taller and heavier than those from southern schools (P ＜ 0.05).There was no difference between students from northern and southern schools in BMI.Compared with the domestic average levels of height,weight and chest circumference of teenagers aged 14 to 17,students of teenager aviation schools were higher,but there was no difference in weight or chest circumference.The average circumferences of the chest,neck,left upper-arm,right upper-arm,waist,hip,left thigh and right thigh were (83.1 ± 5.06),(34.7 ±3.07),(25.2±2.33),(25.5 ±2.30),(73.4 ±6.73),(89.7 ±5.89),(50.1 ±5.22),and (50.2 ±5.27)cm,respectively.According to the data,students from northern schools had a bigger chest circumference and thigh circumference but a smaller neck circumference and upper-arms circumference than those from southern schools (P ＜ 0.05).The correlation coefficient between BMI and the circumferences of the chest,neck,left upper-arm,right upperarm,waist,hip,left thigh and right thigh was 0.2201,0.1066,0.2466,0.2499,0.2291,0.2149,0.2299,0.2264,respectively.All of them were statistically significant (P ＜ 0.0001).Conclusion Load resistance related parameters of students in teenager aviation schools are not different from the domestic levels,which points to the urgent need for load resistance ability training for these students.Some parameters vary between areas.BMI is positively related to those load resistance parameters.Based on regional variations and regularities found in this study,specialized load resistance ability training could be made more efficient.

Since the outbreak of Novel Coronavirus Pneumonia(NCP), hospitals have taken the fight against the virus as its own responsibility, and keep standing in the front line of epidemic prevention and control. The continuous input of anti-epidemic forces in hospitals also brings challenges to the medical supplies support, including the management of protective supplies and the maintenance of medical equipment. In the face of increasing security pressure, the medical materials support team broke the game on multiple fronts. Firstly, the team implements active material procurement strategy, sets material distribution priority according to risk level, releases materials uniformly based on stock and use, and implements traceability management of donated materials to ensure material supply. Secondly, centralized allocation management of equipment, emergency installation, advanced maintenance and emergency maintenance work is effectively completed. Thirdly, disinfection strategies for items and equipment are developed safely and effectively with the aid of disinfection equipment functions. At last, personnel management and training have been strengthened. These measures have provided strong support for the orderly prevention and control of the epidemic.

OBJECTIVE: To explore the effects of cadmium chloride( CdCl_2) on DNA single strand breaks and the production of 8-hydroxy-2'-deoxyguanosine( 8-OHdG) in human embryonic kidney epithelial cells( HEK cells). METHODS: HEK cells in logarithm growth phase were divided into 5 groups and incubated with the different concentrations of CdCl_2( 0. 0,2. 5,5. 0,10. 0 and 20. 0 μmol/L) for 24,48 and 72 hours in vitro. After harvesting the cells,DNA single strand breaks was tested by single cell gel electrophoresis,and the level of 8-OHdG was measured using the enzyme linked immunosorbent assay. RESULTS: The Olive tail moment was statistically significant in the main effect of CdCl_2 exposed HEK cells( P < 0. 01). Among them,when HEK cells were exposed to 5. 0 μmol / L of CdCl_2,the Olive tail moment began to have a statistical significant increasing trend compared with the 0. 0 μmol / L group( P < 0. 05); when CdCl_2 concentration was 2. 5-10. 0 μmol / L,the Olive tail moment lengthened with the increasing dose of cadmium exposure,showing a doseeffect relationship( P < 0. 05). The tail DNA% was statistically significant in the interaction between exposure treatment and exposure time in HEK cells( P < 0. 01). Among them,when CdCl_2 concentration was at 2. 5-10. 0 μmol / L at 24 hours time point and 5. 0-20. 0 μmol / L at 48 hours time point,the tail DNA% raised with the increasing dose of cadmium exposure,showing a dose-effect relationship( P < 0. 05). The tail DNA% at 3 time points of 24,48 and 72 hours after exposure to 20. 0 μmol / L of CdCl_2 in HEK cells increased with the increasing time of cadmium exposure,showing a timeeffect relationship( P < 0. 05). The level of 8-OHdG had statistical significance in the main effect of CdCl_2 exposure treatment in HEK cells( P < 0. 05). Among them,the level of 8-OHdG was first significantly increased only after exposure to 10. 0 μmol / L CdCl_2 compared with the 0. 0 μmol / L group( P < 0. 05). After treatment with Ca Cl2,there was no doseeffect relationship and time-effect relationship found between the cadmium chloride exposure and tail length as well as the tail / head length ratio and 8-OHdG level. CONCLUSION: To a certain extent,CdCl_2 exposure may cause both DNA single strand breaks and 8-OHdG production in HEK cells. Compared with 8-OHdG,the DNA single strand breaks show more significant change with a lower dose of cadmium treatment,which may be related to its higher sensitivity to cadmium toxicity than 8-OHdG.