• Korean Journal of Poultry Science
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• v.47 no.2
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• pp.83-93
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• 2020

The purpose of this study was to evaluate the effects of stocking density on feather condition, egg quality, blood parameters, and corticosterone levels of laying hens reared in conventional cages. A total of 500, 28 weeks-old Hy-Line Brown laying hens were evenly assigned to two stocking densities (750 and 500 ㎠/bird). There were 50 replicates of each treatment, each consisting of 750 ㎠/birds (n=6) or 500 ㎠/bird (n=4) birds in a cage, respectively. We observed an increase in the laying period of, the group that was assigned 500 ㎠/bird, however, this group experienced significant feather damage when compared with the group allotted 750 ㎠ bird. There was no effect of stocking densities on egg quality. These results suggest that the 500 ㎠/bird stocking density in the conventional cage can negatively affect feather condition and cause the birds to experience more stress than the group allotted 750 ㎠/bird.

• Journal of Life Science
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• v.28 no.10
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• pp.1132-1139
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• 2018

The stability of diverse cellular proteins in eukaryotes is regulated via ubiquitination. Moreover, E3 ligase plays a crucial role in determining substrate specificity and transfers ubiquitins into the substrates during the ubiquitination process. As a type of multi-subunit E3 ligase, cullin4 (CUL4)-based E3 ligase (CRL4) complex is involved in a variety of cellular processes, such as hormonal and stress responses in plants. In spite of several reports on the versatile roles of CRL4 in various signalings in Arabidopsis, CRL4's function in rice has been poorly known. To learn about CRL4-mediated cellular processes in rice in more detail, OsCUL4 that exhibits the highest homology with Arabidopsis CUL4 was isolated, and its expression patterns in various tissues and in response to plant hormones and abiotic stresses were monitored. Exogenous application of ABA or cytokinin increased the transcript levels of the OsCUL4 gene. Moreover, OsCUL4 was significantly upregulated in response to drought and salt stresses. These findings imply that OsCUL4 may be functionally related to ABA- and/or cytokinin-mediated cellular responses. OsCUL4 directly interacted with OsDDB1, an adaptor protein of CRL4, indicating that OsCUL4 can act as a scaffold protein of CRL4. An expression study on the OsCUL4 gene from this report could be used as a starting point to elucidate cellular responses in which a CRL4-mediated ubiquitination process is involved in rice.

• Journal of Life Science
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• v.17 no.3 s.83
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• pp.305-311
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• 2007

Glucocorticoids (GCs) alter metabolism, synaptogenesis, apoptosis, neurogenesis, and dendritic morphology in the hippocampus. To better understand how glucocorticoids regulate these aspects of hippocampal biology, we studied gene expression patterns in the CA3 (Hippocampal pyramidal cell field CA3) and dentate gyrus (DG). Litter-matched Lewis inbred rats treated for 20 days with either 9.5 mg per day sustained-release corticosterone or placebo pellets were compared with high-density oligonucleotide microarray analysis (Rat Neurobiology U34 Arrays, Affymetrix). In placebo-treated rats, 32 genes were expressed at greater levels in CA3 than DG, whereas 3 genes were expressed at great levels in DC than CA3. Regional differences were also apparent in corticosterone-induced changes in the hippocampal transcriptome. Six genes in CA3 and 41 genes in DC were differentially regulated by corticosterone. As per the glucocorticoid effects on gene transcription in the brain, forty three of these genes were upregulated, and 4 genes were downregulated. Genes differentially expressed in hippocampus included those for 13 neurotransmitter proteins, 5 ion channel related proteins, 4 transcription factors, 3 neurotrophic factors, 1 cytokine, 1 apoptosis related protein, and 5 genes involved in synaptogenesis. Interestingly, GCs can have suppressive effects on brain BDNF mRNA transcription, one of the neurotrophic factors. These results indicate the diversity of targets affected by chronic exposure to corticosterone and highlight important regional differences in hippocampal neurobiology.

• Korean Journal of Animal Reproduction
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• v.24 no.3
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• pp.249-254
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• 2000

This study was carried out to investigate the possibility of dehydroepiandrosterone sulphate(DHEAS) as a stress hormone. Experiment 1) We evaluated the variation of DHEAS levels of long-term(30minutes a day fur 3 weeks) 37$^{\circ}C$ thermal stressed mice compared with that of cortisol. Serum concentrations of cortisol and DHEAS were measured by radioimmunoassay(RIA). Cortisol levels were not significantly altered both LW(Long-term stressed group, mice were killed without rest) and LR(Long-term stressed group, mice were killed after 4 days' rest) compared with control group, but DHEAS levels were decreased in LW compared with control group(p<0.05), and it kept a sustained difference after 4 days' rest(LR)(p<0.05). Experiment 2) We evaluated the changes of DHEAS levels on term of stress and rest. As stress term was longer, serum DHEAS levels were decreased and also kept a sustained difference after 10 days' rest compared with control group(p<0.05). These results suggest that cortisol has difficulty in taking an accurate measurement after extinction of stimuli, whereas DHEAS is more accurate and stable. Thus, this study implies that DHEAS is a stress-related hormone.

• Journal of Plant Biotechnology
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• v.44 no.1
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• pp.61-68
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• 2017

Gibberellic Acid-Stimulated Arabidopsis (GASA) genes are involved in plant hormone signaling, cell division and elongation, as well as in responses to stress conditions in plants. In this study, we isolated a GASA gene from hybrid poplar (Populus alba ${\times}$ P. glandulosa) and analyzed its physiological phenotype and molecular functions in poplar. PagGASA cDNA encodes a putative protein composed of 95 amino acids containing an N-terminal signal peptide and a conservative cysteine-rich C-terminal domain. Southern blot analysis revealed that one or two copies of the PagGASA are present in the poplar genome. The PagGASA transcripts were highly detected in flowers and roots. Moreover, the expression of PagGASA was induced by growth hormone (gibberellic acid) and stress hormones (abscisic acid, jasmonic acid, and salicylic acid). By using transgenic analysis, we showed that the upregulation of PagGASA in poplar provides high tolerance to drought stress. Therefore, our results suggest that PagGASA plays an important role in drought stress tolerance via stress-related plant hormone signaling in poplar.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.3
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• pp.103-108
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• 2016

In daily life, humans get stress very often. Stress is one of the important factors of healthy life and closely related to the quality of life. Too much stress is known to cause hormone imbalance of our body, and it is observed by the brain and bio signals. Based on this, the relationship between brain signal and stress is explored, and brain signal based stress index is proposed in our work. In this study, an EEG measurement device with 32 channels is adopted. However, only two channels (FP1, FP2) are used to this study considering the applicability of the proposed method in real enveironment, and to compare it with the commercial 2 channel EEG device. Frequency domain features are power of each frequency bands, subtraction, addition, or division by each frequency bands. Features in time domain are hurst exponent, correlation dimension, lyapunov exponent, etc. Total 6 subjects are participated in this experiment with English sentence reading task given. Among several candidate features, ${\frac{{\theta}\;power}{mid\;{\beta}\;power}}$ shows the best test performance (70.8%). For future work, we will confirm the results is consistent in low price EEG device.

• Korean Journal of Poultry Science
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• v.47 no.4
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• pp.219-227
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• 2020

As the earth's average temperature rises, crop and livestock productions are at risk. Chickens are sensitive to heat stress, and increased temperatures may have adverse effects on their production performance and animal welfare. Reliable stress measurements are crucial for heat stress adaptation. Therefore, various measurement methods and biomarkers are used to evaluate poultry stress levels. Heat shock proteins (HSPs) are heat sensitive biological markers that are highly expressed under stress, thereby acting as a cellular thermometer. HSPs also have chaperone activity, which protects cells from heat stress. This review details the role of HSP70 as a molecular chaperone and biomarker for heat stress, which is important for breeding climate-adaptable, thermo-tolerant poultry.

• Korean Journal of Animal Reproduction
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• v.24 no.1
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• pp.109-113
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• 2000

This study was carried out to investigate the effect of short-term thermal stress on the serum concentrations of cortisol and DHEAS in BALB / c male mice. Cortisol and DHEAS concentrations in serum were measured by radioimmunoassay(RIA). We found there were significantly increased in the cortisol levels in 30 min-stressed group(T30) compared with control group(p＜0.01), and then declined without significance in 120 min-stressed group (T120) compared with T30. By contrast, DHEAS levels were decreased without significance in both T30 and T120 compared with control group. Though short-term thermal stress, the continuous decline of DHEAS levels were observed. These results show that short-term thermal stress affects the serum levels of cortisol and DHEAS in mice. Furthermore, we found that DHEAS is a stress-related hormone and will be able to utilize as a stress marker.

• Journal of Korean Biological Nursing Science
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• v.6 no.1
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• pp.5-15
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• 2004

목적 : 이 연구는 항암제를 투여받는 여성암환자에서 발반사마사지가 스트레스반응(활력징후, 코티졸)과 면역반응에 미치는 효과를 평가하기 위함이다. 방법 : 11명의 여성암 환자를 임의로 표출한 후 단일군 전후실험설계로 진행하였다. 종속변수는 스트레스 반응으로 활력징후(수축기 혈압, 이완기 혈압, 맥박수, 호흡수)와 혈중 코티졸, 면역반응으로 림프구 아군(CD3, CD4, CD8, CD19)과 자연살세포(NK cells)이며, 독립변수는 발반사마사지이었다. 중재 전후 종속변수의 변화를 보기 위해 Wilcoxon signed rank test를 실시하였다. 결과 : 중재 전에 비해 중재 후 수축기 혈압, 이완기 혈압, 맥박수, 혈중 코티졸치, CD4와 CD19는 유의한 변화를 보였으나 호흡수, CD3, CD8, 그리고 자연살세포는 유의한 변화를 보이지 않았다. 결론 : 이러한 연구결과는 발반사마사지가 항암화학요법을 받는 여성암 환자의 스트레스 호르몬과 면역관련세포에 영향을 보였지만 표본수가 작고 중재가 1회에 그쳤기 때문에 이러한 단점을 보완한 추후연구를 통해 발반사마사지의 효과를 좀더 잘 규명할 수 있을 것이다.

• Journal of Life Science
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• v.24 no.2
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• pp.196-208
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• 2014

During the life cycle of plants, water deficit leads to an adverse effect on its growth and development. To increase the productivity of crops, overcoming such drought stress is one of the most important issues in the field of plant study. Among plant hormones, the phytohormone, abscisic acid (ABA) plays a crucial role in eliciting resistance to drought stress as well as in multiple developmental processes, such as seed germination, stomatal closure, and seedling growth. Therefore, further understanding of the ABA-mediated signal transduction pathway in plants is an effective strategy to generate drought-tolerant plants. Posttranslational modification, such as phosphorylation and ubiquitination, is an efficient mechanism for plants to acquire quick adaptation against environmental stress conditions since this process directly affects pre-existing signaling components by modulating protein activity and stability. Here, recent reports on ABA signaling are reviewed, especially focusing on ABA transport, perception, signaling, and posttranslational modification in ABA-mediated cellular responses. Also, we present future prospects on how the control of such a mechanism can be applied to generate useful agricultural crops.