• Journal of agriculture & life science
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• v.53 no.4
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• pp.19-28
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• 2019

This study was conducted to investigate the effect of nutrient solution strength and duration of nutrient starvation on the growth and development of strawberry (Fragaria x ananassa Duch.) 'Maehyang' and 'Sulhyang' at the flowering stage. Cuttings of runner plants were stuck on November 23th, 2017 and were covered with a layer of black plastic film to block light from penetrating and keep the relative humidity high. The black plastic film was removed after 16 days and rooted plants were cultivated for one month with irrigation of water. The Yamazaki nutrient solution with an electrical conductivity (EC) of 1.85 or 3.71 dS·m-1 (1x or 2x ionic strength, respectively) and pH 5.55 was fed to plants after either 0 (control), 1, 3 or 5 weeks of nutrient starvation to the end of experiment. Plant height in both cultivars decreased gradually with the increase in duration of nutritional starvation. The earlier the nutritional starvation started, the smaller the shoot fresh weight of 'Maehyang'. Hence the greatest shoot fresh weight was obtained in the control which was supplied with the nutrient solution continuously. Shoot fresh weight of 'Sulhyang' was the greatest in 1x ionic strength and one week of nutrient starvation before planting. Although number of flowers on the first flower cluster of 'Maehyang' and 'Sulhyang' showed no significant differences, 'Maehyang' had the greatest number of flowers in the 2x ionic strength solution and one week of nutrient starvation before planting, while 'Sulhyang' had that in the 1x ionic strength treatment. These results suggest that it is considered effective to supply a nutrient solution at a low concentration for a short period of time for increasing the number of flower differentiated on the first flower cluster in both cultivars.

• BMB Reports
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• v.51 no.7
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• pp.344-349
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• 2018

Therapeutic applications of mesenchymal stem cells (MSCs) are limited due to their early death within the first few days of transplantation. Therefore, to improve the efficacy of cell-based therapies, it is necessary to manipulate MSCs so that they can resist various stresses imposed by the microenvironment. Moreover, the role of superoxide dismutase 3 (SOD3) in regulating such survival under different stress conditions remain elusive. In this study, we overexpressed SOD3 in MSCs (SOD3-MSCs) and evaluated its effect under serum starvation conditions. Nutritional limitation can decrease the survival rate of transplanted MSCs and thus can reduce their efficacy during therapy. Interestingly, we found that SOD3-MSCs exhibited reduced reactive oxygen species levels and greater survival rates than normal MSCs under serum-deprived conditions. In addition, overexpression of SOD3 attenuated starvation-induced apoptosis with increased autophagy in MSCs. Moreover, we have demonstrated that SOD3 protects MSCs against the negative effects of serum deprivation via modulation of AMP-activated protein kinase/sirtulin 1, extracellular signal-regulated kinase activation, and promoted Forkhead box O3a trafficking to the nucleus. Taken together, these results demonstrate that SOD3 promotes MSCs survival and add further evidence to the concept that SOD3-MSCs may be a potential therapeutic agent with better outcomes than normal MSCs for various diseases involving oxidative stress and compromised MSCs survival during therapy.

• Korean Journal of Environmental Biology
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• v.38 no.2
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• pp.315-322
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• 2020

A 210-day experiment was conducted to examine the effects of starvation on survival, the gonadosomatic index (GSI), hepatosomatic index (HSI), and the intestinosomatic index (ISI), and histological changes in the renal tubule epithelium, midgut epithelium, and hepatocytes in Far Eastern catfish (Silurus asotus). The survival rate decreased to 92.2±0.47% in the fed group and 74.4±2.59% in the starved group during the 210-day experimental period. GSI, HSI, and ISI were lowest in the starved group (p<0.05). The hepatocyte nuclear area, hepatocyte cell area, the nuclear height of the midgut epithelium, and the nuclear height of the kidney were highest in the fed group (p<0.05). The hepatocyte nuclear area, nuclear height of the midgut epithelium, and nuclear height of the kidney were lowest in the starved group(p<0.05). The numbers of melano-macrophages (MMs) found in the kidney cells increased during starvation in this species. This suggests that thinner body cavity regions, the contraction of hepatocyte nuclear sites, and the spreading of kidney cell MMs in this species could be used as alternative indicators for identifying starvation conditions. Therefore, the results from our study provide accurate indications of the nutritional status of Far Eastern catfish.

• Korean Journal of Environmental Biology
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• v.39 no.1
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• pp.55-67
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• 2021

A 210-day experiment was conducted to examine the effects of starvation on survival, external morphometric traits, and sectioned morphometric traits in Far Eastern catfish(Silurus asotus). The survival rate decreased to 92.2±0.47% in the fed group and to 74.4±2.59% in the starved group. Eight dimensions of Ls, DALPO/Ls, DADOP/Ls, ED/Ls, CH/Ls, BDAA/Ls, BDMA/Ls, and BWAA/Ls showed significant differences (p<0.05), and 16 other dimensions of DALAD/Ls, DPDPL/Ls, HPLAA/Ls, HALAV/Ls, HALOP/Ls, DAUPO/Ls, DADAV/Ls, DADAA/Ls, Max BL/Ls, Man BL/Ls, LD/Ls, HWOP/Ls, DAUF/HL, DAUS/HL, IW/HL, and DAUE/HL were not significantly different among the initial, fed, and starved groups (p>0.05). The fed group showed higher total height (THX), wider width (WX), and larger area (AX) than those of the starved group in each body section. This research provides information on the morphometric traits and body sections of starved Far Eastern catfish. These results can be used as a basic guide to indicate nutritional status and assist in aquaculture methods for Far Eastern catfish. Moreover, the methods used in this study were considered helpful because the survey analysis method can be used to investigate information on the nutritional status of other fish species.

• Korean Journal of Ichthyology
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• v.11 no.1
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• pp.33-41
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• 1999

The influence of nutritional conditions on the histological changes of hepatocyte and intestinal epithelium as well as hepatosmatic index (HSI), protein, RNA and DNA concentrations of liver of Rhynchocypris oxycephalus was tested. Although, the starved group showed higher concentrations of protein, DNA and RNA than the fed group, food deprivation resulted in a decrease in the HSI, hepatocyte nucleus size and nuclear height of the intestinal epithelium. The RNA-DNA ratio appears to be a useful index of nutritional status in R. oxycephalus and may be useful for determining if R. oxycephalus is in a period of rapid or slow growth at the time of sampling. Additionally, the data have been interpreted in detail and some biologically important relationships discussed.

• Journal of Marine Life Science
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• v.2 no.1
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• pp.27-33
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• 2017

The effects of starvation on the growth, survival and hepatocyte nuclear size of the just hatched grass puffer, Takifugu niphobles larvae were studied. The total length of the larvae showed increase up to 3 days after hatching (DAH), however, 3th to 6th DAH, the starved group grew, slower than the fed group, significantly. The body weight of the fed group grass puffer showed increase steadily during experimental period. The body weight of the starved group showed increase until 3th DAH, however, after 3th DAH the growth of body weight showed minute decrease. The survival of starved group decreased more significantly lower than that of the fed group and all the larvae died on the 6th DAH (p < 0.05). The nuclear area of the hepatocytes in the starved group were not significantly different from those of the hepatocyte nuclei in the fed group to 3th DAH, however, the starved group showed histological differences with smaller hepatocyte nuclear size compared with the fed group from the 4th to 6th DAH. Results form this study can be used as an indicator of the nutritional status of grass puffer larvae.

• The Korean Journal of Mycology
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• v.10 no.4
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• pp.193-202
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• 1982

The changes of total carbohydrates and trehalose levels during differentiation of A. niger were studied. Aspergillus niger was cultivated in Czapeck-Dox medium by the method of surface culture and shake culture. Total carbohydrates and trehalose were fractionated and determined by the method of Trevelyan and Harrison (1956). Total carbohydrates and trehalose accumulated in A. niger during sporulation. The influences of nutritional starvation on the levels of cellular carbohydrates in A. niger, which was cultivated in each nitrogen, phosphate and glucose limited Czapeck-Dox medium, were studied. The levels of total carbohydrates and trehalose in A. niger cultivated in nitrogen limited medium increased much than those cultured in full medium. The total carborates and trehalose levels in A. niger cultivated in phosphate limited medium increased, but the increases were less than those cultured in nitrogen limitted medium. In glucose limited medium, any changes of total carbohydrates and trehalose levels were not found. It is considered that the biochemical mechanisms responsible for the changes of total carbohydrates and trehalose levels may be related with differentiation of Aspergillus niger.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.2
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• pp.213-222
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• 2015

This study was performed to investigate the dietary habits and satisfaction of school foodservice by high school type (academic high school students (AHSS) : n=200, vocational high school students (VHSS) : n=200). Frequency of skipping breakfast was significantly higher for VHSS compared with AHSS (p<0.001), and reasons for skipping breakfast were significantly high for 'lack of time' and 'habitually' in VHSS (p<0.01). Duration of mealtime was significantly higher for AHSS compared with VHSS (p<0.001). Frequency of snacking was high in both AHSS and VHSS, and after dinner was the most common snack time for AHSS (p<0.001). Most commonly cited methods for improving dietary habits were 'frequently skipping meals' in AHSS and 'irregular meals' in VHSS. Reasons for leaving leftover foods were 'no taste' in AHSS and 'side dish I don't like' in VHSS (p<0.05). Satisfaction of school foodservice was significantly higher for AHSS compared with VHSS (p<0.05). Most commonly cited methods for improving school foodservice were 'varied menu' in AHSS and 'food taste' in VHSS (p<0.05). Commonly cited dietary motivations were 'preference' in AHSS and 'resolving starvation' in VHSS (p<0.001). As preference is an important factor, new menu development and continuous nutritional education should be necessary for menu diversity in order to raise satisfaction by using foods with high preference and superior nutrition.

• Journal of the Korean Society of Food Culture
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• v.3 no.4
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• pp.397-406
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• 1988

The changes in the dietary pattern of Koreans during the last one century and its consequences are summarized as follows; 1. Until the beginning of 20th century, Koreans used variety of cereals, vegetables and fruits for their staple food, but the variety has been largely reduced by the agricultural development and urbanized life style. 2. The well balanced traditional dietary pattern of Korean had been deeply deteriorated by the food shortage during the Japanese occupation and Korean war. 3. The deteriorated nutritional condition of Korean was not remedied by the restoration of traditional dietary pattern, but attempted to overcome it by the adoption of Western food habit. 4. The people were trained to eat milk and flour-meals during the starvation of Korean war, and it was continued after Korean war through the animal husbandry promotion policy. 5. The importation of food and feed cereals has been increased rapidly during the economic growth in 1970's and the food self-sufficiency droped below 50%. 6. In 1970's, the food supply pattern of Korean was restored to the level of early 1900, but the consumption of lipid increased extraordinarily. 7. The overconsumption of animal food and lipid continues in 1980's, and it coincides with the rapid increase in the occurence of food related degenerative deseases. 8. The establishment of Korean dietary goal which is based on the traditional dietary pattern is needed.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.10
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• pp.1455-1459
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• 2003

A $2{\times}3$ factorial design was used to study the impact of rearing systems, individual (I) vs. group (G) and different levels of milk/skim milk feeding (three schedules, F1, F2 and F3) on performance of crossbred (Bos indicus ${\times}$ Bos taurus) calves. Six calves (three from each sex) were taken in each group on the basis of their birth weight. All the calves were fed colostrum for three days and thereafter, were allotted to three different milk feeding schedules (F), i.e. milk fed upto 8 weeks of age (F1), milk upto 4 weeks followed by 50% (F2) and 100% (F3) replacement of milk with skim milk in the next 4 weeks. Calf starter and cereal green fodder were fed ad libitum to all the calves beginning from second week of age. A digestibility trial was conducted at 15th week of age to assess nutrient utilization during postweaning period. The digestibilty of dry matter (DM), organic matter, total carbohydrate, ether extract and crude protein (CP) were nonsignificant between the rearing systems and the feeding schedules. There was significantly higher digestibility of NDF and ADF in G than I and in F3 than F1 and F2. The concentration CP and total digestible nutrients of the diet ranged from 17.18 to 17.75% and 66.32 to 70.14%, respectively. The DM intake (kg/100 kg body weight) ranged from 1.74 to 2.14 kg during 0 to 8 weeks and 3.19 to 3.41 kg during 0 to 14 weeks of age. The effects during postweaning phase (9-14 weeks of age) showed increased performance in group housed calves compared to individually housed ones with a superior average daily gain (590 vs. 443 g) and dry matter intake (1.79 vs. 1.64 kg). Above all, replacement of milk with skim milk at 50% level after 4th week followed by complete removal after 6th week of age (F2) seemed to suit better in coping with immediate energy starvation due to sole feeding of skim milk (F3) and they performed the best under group housed system of rearing.