• The Korean Journal of Physiology and Pharmacology
• /
• v.14 no.2
• /
• pp.113-118
• /
• 2010

The sensory system is developed and optimized by experiences given in the early phase of life in association with other regions of the nervous system. To date, many studies have revealed that deprivation of specific sensory experiences can modify the structure and function of the central nervous system; however, the effects of sensory overload remains unclear. Here we studied the effect of overloading the taste sense in the early period of life on the synaptic plasticity of rat hippocampus and somatosensory cortex. We prepared male and female Sprague Dawley rats with ad libitum access to a 0.1% saccharin solution for 2 hrs per day for three weeks after weaning on postnatal day 22. Saccharin consumption was slightly increased in males compared with females; however, saccharin intake did not affect chow intake or weight gain either in male or in female rats. We examined the effect of saccharin-intake on long term potentiation (LTP) formation in hippocampal Schaffer collateral pathway and somatosensory cortex layer IV - II/III pathways in the 6-week old saccharin-fed rats. There was no significant difference in LTP formation in the hippocampus between the control group and saccharin-treated group in both male and female rats. Also in the somatosensory cortex, we did not see a significant difference in LTP among the groups. Therefore, we conclude that saccharin-intake during 3~6 weeks may not affect the development of physiological function of the cortical and hippocampal synapses in rats.

• Development and Reproduction
• /
• v.2 no.2
• /
• pp.205-212
• /
• 1998

A sodium-independent facilitative glucose transporter 1 (Glut1) is a major route by which glucose can be transported across the plasma membrane of mouse embryo. Although it has been known that insulin-like growth factor-I (IGF-I) promotes glucose transport into the mouse embryo, whether IGF-I directly regulates transcription of Glut1 has been uncovered in mouse preimplantation embryo. This study was aimed to elucidate the role of glucose and IGF-I in development and Glut1 expression in preimplantation mouse embryo. Two-cell embryos developed in blastocyst regardless of the glucose in the presence of pyruvate. IGF-I significantly increased the number of blastomeres in the mid-blastula. Deprivation of glucose did not affect the amount of Glut1 transcripts in morula cultured from 2-cell embryo. IGF-I potentiated Glut1 expression in morula cultured from 2-cell embryo even in the absence of glucose. Taken together, it is concluded that depletion of glucose does not promote Glut1 expression the in morula cultured form 2-cell embryo, and that increment of Glut1 expression possibly mediates embryotropic effect of IGF-I on preimplantation mouse embryo.

• Korean Journal of Social Welfare
• /
• v.55
• /
• pp.155-179
• /
• 2003

This paper compares two indicators, economic development and social condition, to find a better way to measure the level of social welfare development. The results show that social condition is more adequate indicator than economic development. The social condition has high correlation with the development of social welfare in all the 78 countries as well as in five groups of countries when the economic development is controlled. The comparison of two indicators reveals important findings. Among other things, the higher the level of social condition compared with economic development, the larger the social welfare expenditure. This tendency is particularly strong among the western European countries and former socialist countries. This result implies that the macro-level policy of social redistribution is also important for the development of social welfare in addition to micro-level policy of income redistribution. As we expected, the results show that the level of Korean social welfare development is very low. Considering our levels of economic development and social condition, predicted social welfare expenditure from regression model is at least 17% of GDP, but we are spending only 30% of this predicted expenditure. Another serious problem in Korean social welfare is unbalanced expenditure between social insurance and public assistance. On the basis of these results, this paper suggests three implications for social policy to improve Korean social welfare: First of all, the gap between predicted and actual expenditures should be closed to improve the minimum level of social welfare. Secondly, the level of social condition itself should be improved to increase the public awareness of social welfare. Finally, the wide difference in expenditure between universal and selective social welfare programs should also be removed to decrease the relative deprivation of the poor.

• Asian-Australasian Journal of Animal Sciences
• /
• v.24 no.7
• /
• pp.974-981
• /
• 2011

This study was designed to re-evaluate the dietary methionine requirement by means of the plasma methionine and ammonia concentrations in surgically modified rainbow trout, Oncorhynchus mykiss. A total of 35 rainbow trout averaging $505{\pm}6.5$ g (initial body weight, mean${\pm}$SD) were randomly distributed into seven groups with five fish in each group. After 48 h of feed deprivation, each group of fish was fed one of seven L-amino acid based diets containing 0.5% cystine and graded levels of methionine (0.25, 0.40, 0.50, 0.60, 0.70, 0.80 or 0.95% of diet, dry matter bases) by intubation at 1% body weight on dry matter basis. Blood samples were taken at 0, 5 and 24 h after intubation. Post-prandial plasma free methionine concentrations (PPmet, 5 h after intubation) and post-absorptive plasma free methionine concentrations (PAmet, 24 h after intubation) of fish fed diets containing 0.60% or higher methionine were significantly (p<0.05) higher than those of fish fed diets containing 0.50% or lower methionine. PPmet and PAmet in fish fed diets containing 0.60% or higher methionine were not significantly different except PPmet of fish fed diet containing 0.95% methionine. Post-prandial plasma ammonia concentrations (PPA, 5 h after intubation) of fish fed diets containing 0.70% or higher methionine were significantly higher than those of fish fed diets containing 0.60% or lower methionine, and PPA of fish fed diets containing 0.25 and up to 0.60% methionine were not significantly different from each other. Broken-line model analyses on PPmet, PAmet, and PPA indicated that the dietary methionine requirement of rainbow trout was between 0.59 (1.69) and 0.67 (1.91) % of diets (% dietary protein bases) when the diets contained 0.5% cystine.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.45 no.4
• /
• pp.467-473
• /
• 2016

This study was designed to investigate whether consumption of onion wine can reduce serum biomarkers of ethanol-induced fatty liver in rats. Male Sprague-Dawley rats were initially trained for meal feeding to prevent reduction of food intake. After the training period, rats were weight-matched and assigned to the following three groups: 1) a control group fed a control liquid diet containing maltose-dextrin, 2) an ethanol group fed an ethanol liquid diet with 95% ethanol, and 3) an onion wine group fed the same ethanol liquid diet but containing onion wine extract at 1 mL/d/group. All three groups were fed daily for 6 weeks. At 0, 3, and 6 weeks, blood was collected via the orbital sinus following overnight food deprivation and terminally organs collected. Blood lipids and transaminase activities significantly increased in the ethanol-fed group but significantly reversed in the onion wine-fed group. The hepatic levels of fat and cholesterol at 6 weeks were significantly elevated by ethanol administration but significantly reduced by onion wine. These findings indicate that onion wine may ameliorate ethanol-induced fatty liver by lowering hepatic and blood lipid levels.

• The Korean Journal of Food And Nutrition
• /
• v.23 no.4
• /
• pp.526-530
• /
• 2010

Isopentenyl diphosphate(IPP) isomerization to dimethylallyl diphosphate(DMAPP) is an important step for the efficient production of isoprenoids such as lycopene, ${\beta}$-carotene, astaxanthin, etc. The type II isopentenyl diphosphate isomerase gene from Synechocystis sp. PCC6803(sll1556, Syidi2) was cloned and expressed in Escherichia coli $DH5{\alpha}$. When E. coli $DH5{\alpha}$ harboring lycopene synthesis genes, crtE, crtB, and crtI and mevalonate pathway genes, MvK1, MvK2, and Mvd, was cultured on LB medium containing mevalonate, the strain grew very slowly be due to the toxicity of isopentenyl diphosphate derived from mevalonate. When Syidi2 was introduced to E. coli $DH5{\alpha}$ harboring the lycopene synthesis genes and mevalonate pathway genes, growth on mevalonate medium was fully restored and the colony showed red color indicating lycopene formation. The growth rate of the mutant strain, E. coli $DH5{\alpha}$(idi::${\Delta}km$), was very slow because of IPP accumulation and DMAPP deprivation. Ultimately the idi mutant was complemented by introducing the Syidi2 gene.

• Journal of Navigation and Port Research
• /
• v.31 no.8
• /
• pp.629-635
• /
• 2007

Reduced crew performance is frequently cited as a major causal factor in maritime accident causation. Although considerable research has been conducted on the hours of work undertaken by seafarers through interviews and the analysis of records, experimental studies to observe the effects of factors such as high workload, shift patterns, stress, sleep deprivation and disturbance on the cognitive performance of mariners have been limited. Other safety-critical transport industries, such as aviation and rail, have developed fatigue management tools to help manage the work patterns of their operators. Such a tool for mariners would assist shipboard crew, marine pilots and shore management in planning and improving work schedules. The overall aim of this paper is to determine a fatigue factor, which can be applied to human performance data, as part of a software program that calculates total cognitive performance. This program enables us to establish the levels of cognitive performance of a group of marine pilots to test a decision-making task based on radar information. This paper addresses one of the factors that may contribute to the determination of various fatigue factors: the effect of different work patterns on the cognitive performance of a marine pilot.

• Journal of Oriental Neuropsychiatry
• /
• v.28 no.1
• /
• pp.25-38
• /
• 2017

Objectives: The study aims were to evaluate the Anti-stress and Sleep-inductive effects of Yunjogyosim-tang (YJGS) in rats induced by Chronic Mild Stress (CMS). Methods: 25 healthy Rats were randomly divided into 5 groups; Normal, CMS (Control), YJGS 50, YJGS 100, and YJGS 200. All rats except the normal group were exposed to random stress conditions like water deprivation, empty bottles, forced runs on the treadmill, etc. according to the timetable of CSM for 3 weeks. After a week starting the experiment, Rats in YJGS 50, YJGS 100, and YJGS 200 groups were fed orally once a day for 2 weeks. Blood samples were taken afterward from each rat for analysis of Complete blood count, AST, ALT, and glucose levels. Corticosterone, serotonin, and melatonin were measured by ELISA kit. BDNF and $TNF-{\alpha}$ were measured by RT-PCT. Results: 1. Corticosterone levels were lower in YJGS 50, and YJGS 200 groups compared to the control group. 2. Serotonin levels were lower in the YJGS 100 and YJGS 200 groups compared to the control group. 3. Melatonin levels were higher in the YJGS 50 group compared to the control group. 4. Activity levels were higher in the BDNF, and YJGS 50 groups compared to the control group. 5. In the Activity of $TNF-{\alpha}$, YJGS 50 group showed a significant decrease compared to the control group. 6. In the Glucose content, YJGS 50, YJGS 100, and YJGS 200 groups showed a significant decrease compared to the control group. 7. When analyzing leukocytes, monocytes were found to be increased in YJGS 100 and YJGS 200 groups compared to the control group. 8. When analyzing red blood cells, more changes occurred to erythrocytes and thrombocytes in the YJGS 50 and YJGS 200 groups than in the control group. Hemoglobin was significantly increased in the YJGS 100 group and platelet levels were significantly increased in all experimental groups compared with the control group. Conclusions: These results suggest that Yunjogyosim-tang has anti-stress and sleep-inductive effects on rats induced by CMS.

• Journal of the Korean Society of Earth Science Education
• /
• v.11 no.1
• /
• pp.1-20
• /
• 2018

The purpose of this study is to suggest some strategies for integrated science. It also suggests educational strategies through worldview. The directions of most educational policy are based on the deficit model. It is assumed that learners are always lacking in knowledge, and as a result they do not understand properly. However, it is difficult for the public and students to change their attitudes because they do not feel much lacking. For example, the world view of climate change coexists with an optimistic mechanical worldview and an organic and entropy worldview. This study is characterized by the process of expanding awareness of living and fulfillment of knowledge rather than the existing deprivation model. Unconnected knowledge has problems in diversity. It is neither sustainable nor flexible. It is not about eliminating interdisciplinarity but about lowering it. We go into another area with your deep expertise, but we must have a purpose. As a result, not only problem solving but also dynamic feedback of mutual feedback between other domains increases the quality and quantity of knowledge.

• Asian-Australasian Journal of Animal Sciences
• /
• v.23 no.9
• /
• pp.1174-1183
• /
• 2010

In goats fed on dry forage twice a day, an esophageal fistula was used to investigate the physiological factors present in the marked suppression of dry forage intake that occurs after 40 min of feeding. The animals used in this study were five large-type male esophageal- and ruminal-fistulated goats. Roughly crushed alfalfa hay cubes with any large remaining chunks removed were used as feed for this research. The study was conducted under both normal feeding conditions (NFC) and sham feeding conditions (SFC). In the NFC control, the esophageal fistulae were closed by plugs and the animals ate dry forage in the normal manner. In the SFC treatment, before starting the experiment the plugs for closing the esophageal fistula were removed and the cannulae for collecting boluses were fitted into the fistulae. Therefore, the esophageal boluses were removed via an esophageal fistula before they entered the rumen. In the NFC control, eating rates sharply decreased in the first 40 min of feeding and were subsequently maintained at low levels. However, eating rates in the SFC treatment remained high after 40 min of the feeding period had elapsed and the goats ate continuously during the 2 h feeding period. In comparison with the NFC control ($1,794{\pm}203.80\;g$/2 h), cumulative dry forage intake in the SFC treatment ($3,182{\pm}381.69\;g$/2 h) was 77.4% greater (p<0.05) upon conclusion of the 2 h feeding period. In the SFC treatment, cumulative bolus output ($6,804{\pm}469.92\;g$/2 h) was about twofold the cumulative dry forage intake due to cumulative salivary secretion volume ($3,622{\pm}104.13\;g$/2 h) upon conclusion of the 2 h feeding period. The result indicates that large amounts of secreted saliva during dry forage feeding act in conjunction with consumed feed to form the ruminal load responsible for ruminal distension. The increased plasma total protein concentrations were higher in the SFC treatment than in the NFC control. However, plasma and ruminal fluid osmolalities increased in the NFC control during and after feeding but were mostly unchanged in the SFC treatment. In comparison with the NFC control ($3,440{\pm}548.04\;g$/30 min), thirst level in the SFC treatment ($1,360{\pm}467.02\;g$/30 min) was 60.5% significantly less (p<0.05) upon conclusion of the 30 min drinking period. The results of the present study indicate that In the second hour of the 2 h feeding period, dry forage intake is regulated by factors produced when boluses enter the rumen.