Effects of Long-term Intermittent Oxygen Administration on the Cognitive Function in Rats / 대한마취과학회지

BACKGROUND: Several studies have demonstrated that the transient administration of oxygen improves cognitive performance. However, the effect of long-term oxygen administration remains unknown. This study investigated the impact of long-term oxygen administration on cognitive enhancement. METHODS: Six week old Sprague-Dawley rats (n = 46) were randomly allocated to one of three groups: the control (Control; n = 15), 30 min/day oxygen administration (Oxy30min; n = 16) and 60 min/day oxygen administration groups (Oxy60min; n = 15). The rats in all three groups were administered air or oxygen for 10 weeks. The Morris water maze test was employed to assess the latency (L & Lt), dwelling time (DT) and the total fraction above the mean dwelling time (FmDT) for cognitive performance. RESULTS: Compared to the control group, the Oxy30min and Oxy60min groups showed no differences in their L and Lt. There was a dose-response trend due to oxygen administration. Compared to the control group, the Oxy60min group had a significantly improved DT (P< 0.05). The FmDT also significantly increased in both of the oxygen administration groups, which also showed a dose-response trend (P<0.05). CONCLUSIONS: The present results suggest that long-term (10 weeks) oxygen administration can dose-dependently enhance cognitive performance.

The Effects of Inhalation of Essential Oils on the Body Weight, Food Efficiency Rate and Serum Leptin of Growing SD Rats / 간호학회지

PURPOSES: This experimental study was designed to verify the effect of inhalation of essential oils on body weight, feed intake, food efficiency rate and serum leptin. METHODS: The subjects of this study were 90 growing SD rats (46 males and 44 females). They were allocated into one of four groups, the Fennel group, Patchouli group, Bergamot group and control group. The experimental treatment was the inhalation of aromatherapy essential oils which was applied two times a day for 10 minutes each during 8 weeks. To evaluate the effects, body weight, feed intake, food efficiency rate and serum leptin were measured before and after the treatment. The collected data was analyzed by repeated measures of Kolmogorov-smirnov test and Normal Q-Q plot for nomality, Kruskal Wallis test and X2-test for experimental effects with the SPSS program. RESULTS: The food efficiency rate was significantly lower in the Patchouli group and Fennel group than in the Bergamot group and control group (P=.000). No significant group effects were found for SD rat's body weight, feeding amount and serum leptin. CONCLUSION: In conclusion, these findings indicate that the inhalation of essential oils could be effective in lowering the food efficiency rate rather than the feed intake.

Morphological changes in rat testes after Hindlimb Unloading model / 항공우주의학회지

BACKGROUND: The purpose of this study was to examine histological changes of testes induced by hindlimb unloading & position change of testis in mature adult male rats. METHOD: Eight month old (390~410g) 36 male Sprague-Dawley rats were weight-matched assigned to Ground Control (GC), Hindlimb Unloading (HU), Hindlimb Unloading & Testis Tie(HUT), Intra-abdominal Testis(IAT) for 24 days. Daily body weight was watched for status of animal. Testis weight, Seminiferous Tubule Diameter(STD), Seminiferous Tubule Perimeter(STP), Serminiferous Tubule Area(STA), Sertori Cell Height(SCH) were examined in each group. RESULTS: The 24-day hindlimb unloading of HU, HUT and IAT showed no significant change of body weight compared to GC. HUT maintained the weights, STD, STP, STA, SCH of their testes as GC while HU, IAT had significantly decreased the weights, STD, STP, STA of their testes. CONCLUSION: These results support that hindlimb unloading experiment induces serious morphological changes of testes. Therefore, on the hindlimb unloading experiment, IAT should be avoid or the effect of IAT should be correct. It will be necessary to study the pure effect of hindlimb unloading without IAT on the musculoskeltal system and so on which are associated with testosterone.

Effect of Hindlimb Unloading of the Mechanical Properties of Bone in Mature Adult Male Rats: with Emphasis on the Bone Strength / 항공우주의학회지

BACKGROUND: The purpose of this study was to examine site-specific bone strength changes induced by hindlimb unloading in mature adult male rats. METHODS: Eight month old (390-410 g) 26 male Sprague-Dawley rats were weight-mated assigned to either a Ground control (CON) or a Hindlimb Unloading (HU) for 24 days. Daily body weight was watched for status of animal. Weight, BMD, strength, geometry of femur, tibia and humerus were examined in both groups. RESULTS: The 24-day hindlimb unloading of HU showed no significant change of body weight, total bone mineral, and bone geometry compared to CON. HU showed that the upper limb had maintained total bone mineral, bone geometry, and bone mechanical strength compared to CON. The hindlimb of HU had significantly decreased bone strength and ultimate stress (F/B) compared to CON. DEXA analysis of BMD and BMC in HU showed inconsistent changes at femur and tibia, although a relatively constant increase was shown in humerus. In HU rats, mechanical stress testing of compulsive fracture showed that more significant decreases in UL (ultimate load) and ultimate stress (F/B) was seen in femur than in tibia. CONCLUSION: These results support the theory that hindlimb unloading contribute to deleterious effects in femur rather than in tibia. It induced higher loss of mechanical bone strength in femur. In testing for BMD, pQCT, 2D, or 3D is recommended. DEXA is not recommended because it has inconsistent results and limitation with respect to the characteristics of area BMD (g/cm2) as a surrogate of volume BMD (g/cm3).

A Survey of Health-related Lifestyle of the ROKAF Pilots / 항공우주의학회지

BACKGROUND: The present study was undertaken to know health-related lifestyles of Republic of Korea Air Force (ROKAF) pilots and to investigate prevalence of obesity of them.METHODS: 1284 KAF pilots were checked their height, weight, and body composition (% body fat). We also tried questionnaires on their health-related lifestyles which included the effort to be healthy, whether they know weight training is beneficial to G-tolerance, exercise habit and smoking history. RESULTS: Pilots' attitude for health promotion was relatively passive. Many of them know that weight training is good for their G-tolerance, but only 8.1% of the pilots carried out that training. They engaged much more in aerobic training, and also fighter pilots are less participated in weight training than transport pilots. The prevalence of obesity (29.4%) determined by bioelectrical impedance analysis was much higher than that assessed on the basis of height and weight (BMI, body mass index). It is suggested that many pilots who were normal in BMI have abdominal or visceral obesity. CONCLUSION: The health promotion program and physical conditioning program related to increasing G tolerance of KAF pilots flying high-performance aircraft are very important. These programs must be organized and progressed with flight surgeon and Aeromedical center in Chung-ju as leaders.

The Status of Nutrient and Food Intakes and the Nutritional Knowledge in Adolescent Rhythmic Gymnasts

The objectives of this study were to investigate 1) the foods intake as well as nutrients intake, 2) the nutritional knowledge, and 3) the relations between the foods and nutrients intakes and nutritional knowledge in adolescent rhythmic gymnasts (RGs). The results are summarized as follows. Average daily intakes of energy, calcium, iron, vitamin A, vitamin B1, vitamin B2 and niacin were in 45 - 74% of the RDAs for Koreans. Average daily energy intake was only about 50% of energy expenditure by physical activities. Average daily intakes of each food group were generally lower, but intakes of breads and confectionaries, sugar and sweets, milks and dairy products, and instant foods were higher in the RGs compared to the nonathletic students of the same age from the National Health and Nutrition Suvey. The contribution of empty-calorie foods such as breads and confectionaries, beverage and instant foods to the major energy nutrients were high. Mean of total nutritional knowledge score of RGs was 28.4 of total score 50. In categorical score of nutritional knowledge, the RGs make a best score on food sources and they get the lowest marks for food exchange. Among the nutrients, intakes of crude fiber, animal Fe, Na, K, vitamin A, carotene, vitamin B1, niacin and vitamin C and, among the food groups, intakes of mushrooms, fruits and meats had relations with one of the total or categorical nutritional knowledge scores in the RGs. In conclusion, nutritional status of adolescent RGs was poor due to their unbalanced diet composed of empty-calorie foods, and their undesirable food intake pattern was supposed to be related to the low nutritional knowledge score of them. These results indicate that the RGs should be given more nutritional knowledge to improve their nutritional status and the exercise performance.

Analysis of Risk Factors on the G-induced Loss of Conscious in ROKAF Pilots / 항공우주의학회지

Of all the aeromedical treats to flying safety, G-induced loss of consciousness (G-LOC) must be one of the most important. The present study is undertaken to acquire the physiological normative data (including lifestyle and physical fitness) of KAF pilots and to investigate the factors that will be related with G-LOC. From 15 May through 27 Nov 2000, 464 KAF pilots underwent high G training and flight performance tests at the Aeromedical Research and Training Center are checked CBC, total cholesterol, PFT, physical fitness battery tests-muscular strength, muscular endurance, power, and flexibility. High G training and 2 kinds (before and after the G-training) of questionnaire were tried. Pilot's attitude for health promotion was relatively passive and the proportions as of high and borderline risk for atherosclerosis in total cholesterol level were 4.98% and 22.1%, respectively. 17.6% of the pilots had G-LOC and three quarters of them fell into G-LOC within the first 5 seconds. Variables showing significant correlation (p<0.05) with G-LOC were as follows; height, age, total flying time, and high G-training times. Trunk extension had positive correlation and curls ups had negative correlation, but the reasons are needed more following study. Also, the judgments of pilots and a supervisor in skillfulness of L1 maneuver were significant with G-LOC.