• Development and Reproduction
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• v.5 no.1
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• pp.1-8
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• 2001

Golden hamsters show the reproductive activity that is determined by the photoperiod (length of light per day). Photoperiod is an environmental factor that is predictable through an entire year. The hamsters are sexually active in summer during which day length exceeds night time. The critical length is at least 12.5 hours of light in a day where reproductive function is maintained. The information of photoperiod is mediated by the pineal gland because removal of pineal gland blocks the influence of photoperiod on reproductive activity. The hamsters without pineal gland maintain sexual activity and promote it in a situation that suppresses gonadal activity. The pineal gland secretes melatonin that reflects the photoperiod. The appropriate administrations of melatonin into both pineal intact and pinealectomized hamsters lead to a gonadal reression. The results suggest that melatonin constitutes a part of control mechanism whereby environmental information is transduced to neuroendocrine signal respensible for the functional integrity of the reproductive system. Despite of the intense studies, the action site of melatonin is on the whole unknown. It is mainly due to the lack of acute efffct of melatonin on the secretion of reproductive hormones. However, sexually regressed animals display the low levelsof gonadotropins and the augmentation of the hypothalamic gonadotropin-releasing hormone (GnRH) content, implying that the antigonadotropic effects either by photoperiod and/or by the treatment of melatonin are mediated by the GnRH neuronal system. The action mechanism by which melatonin exerts its effect on GnRH neuron needs to be investigated. Recent cloning of melatonin receptor will contribute to examine various and putative potencies of melatonin via its anatomical identification and the action mechanism of melatonin on target tissues at the molecular level.

• Korean Journal of Animal Reproduction
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• v.27 no.2
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• pp.169-177
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• 2003

This study was conducted to determine effects of polyvinyl alcohol (PVA), fetal bovine serum (FBS) bovine serum albumin (BSA) and epidermal growth factor (EGF) on blastocoel formation, total cell number, apoptosis and apoptosis-related gene expression of porcine diploid parthenotes developing in vitro. The addition of 0.4% BSA to the culture medium enhanced the development of 2-cell stage parthenotes to the blastocysts stage (P<0.01). FBS reduced cell numbers of blastocysts (P<0.01) and increased percentage of apoptosis in the blastocysts (P<0.001). However, while BSA increased cell numbers, it did so only when EGF was present. Either agent on its own had no effect. Similarly, apoptosis in the blastocysts was not influenced by either agent on its own but was reduced when both BSA and EGF were present. Furthermore, semi-quantitative reverse-transcriptase polymerase chain reaction revealed that EGF enhanced the mRNA expression of Bcl-xL in the presence of 0.4% BSA but BSA and EGF alone had no effect, and EGF and/or BSA did not influence Bak gene expression in the blastocyst stage parthenotes. However FBS reduced Bcl-xL mRNA expression (P <0.05) and enhanced Bak expression. This result suggests that apoptosis related genes expression is significantly affected by supplements, which may result in alteration of apoptosis and embryo viability of porcine embryos developing in vitro.

• Analytical Science and Technology
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• v.29 no.6
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• pp.277-282
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• 2016

British Pharmacopoeia (BP 2013), the United States Pharmacopoeia (USP 39) and the Korean Pharmacopoeia (KP XI) contain monographs for the quality control of raw diosmin using high performance liquid chromatography (HPLC). However, official monographs detailing pharmaceutical formulations for diosmin are not available in foreign pharmacopoeias. In the KP XI, ultraviolet-visible (UV-Vis) spectroscopy-which is less specific than HPLC-is reported for the testing of diosmin capsules. In this study, we present an alternative HPLC assay for such testing that is more specific than UV-Vis methods. Method validation was performed to determine linearity, precision, accuracy, system suitability, and robustness. The linearity of calibration curves in the desired concentration range was high ($r^2$>0.999), while the RSDs for intra- and inter-day precision were 0.15-0.29 % and 1.05-1.74%, respectively. Accuracies ranged from 101.2-103.2 %, while the retention time and peak area RSDs were 0.37 % and 0.06 %, respectively. Additionally, the plate number and asymmetry factor values for diosmin were 3591.293 and 1.35, respectively. Since the intermediate-precision and robustness of the assay were satisfactory, this method will be a valuable addition to the Korean Pharmacopoeia (KP XI).

• Ecology and Resilient Infrastructure
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• v.6 no.4
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• pp.191-199
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• 2019

Road development is considered an important factor in invasion and dispersion of ailen plants by damaging the natural ecosystems and connecting the detached landscapes into long tubular structures. In this study, vegetation survey was carried out according to the topographical characteristics of cut slope, fill slope, and flat land at the construction site in order to understand the effect of road developemt on the change of the floristic composition of ailen plants. Road developement projects caused a lot of changes in annual and biennial alien plants because of continuous disturbances. Changes in species composition of alien plants decreased in the cut slope. On the other hand, the ailen palnts of the fill slope increased. The increase or decrease alien plants on flat land were identified depending on where it occurred, and no major trend was found. The cause of these change was driven by unintentionally introduced alien plants. In particular, the cut slope with a high occurence of unintentional ailen plants should not be used as a source of high-risk alien plants such as ecosystem disturbances. Since the transplanted species were intentionally planted by the landscape plan, it was possible to identify colonies from early stages and spread to the nearby flat land. Therefore, in order to minimize the impact of road slope vegetation on the surrounding ecosystem during and after road construction, it is suggested to plant high viability plants in the landscape design during the environmental impact assessment consultation.

• Science of Emotion and Sensibility
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• v.21 no.1
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• pp.3-16
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• 2018

The emergence of the fourth industrial revolution is rapidly changing the conventional society and the industry, eroding the boundaries among the technology, culture, and finance. In the mobility industry, as the engineering-based industry converges with the information technology, the mobile space is changing from mobility or safety-centric space into space where the passengers can consume infotainment or contents services. The contents evaluation of the future mobility is conducted in terms of usability or technology acceptance aspect, but according to the trend analysis, the mobility industries, such as vehicle OEMs, it is necessary to evaluate the emotional or sensibility factors for the development of their future mobile space design. Herein, this research study evaluates which sensibility factor should be evaluated in priority to develop the contents interaction in the future mobile space. Thus, using Patrick Jordan's Four Pleasure Model, the priority evaluation has been conducted among 116 Korean drivers. As a result of the statistical analysis and AHP (Analytic Hierarchy Process), it has been found that first, it is necessary to evaluate psychological, ideological, social and physical sensibility in the respective order, and second, it is necessary to evaluate based on the contents user type.

• Korean Journal of Food Science and Technology
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• v.49 no.5
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• pp.559-566
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• 2017

This aim of this study was to examine the immunomodulatory activities of crude polysaccharides from Perilla frutescens Britton var. acuta Kudo (PCP) in mouse bone marrow-derived dendritic cells (BMDC) and splenocytes. The immunomodulatory activity was determined by cell viability, nitric oxide (NO) production, cell surface marker expression (CD 80/86 and MHC class I/II), and cytokine production in BMDC, and cell viability, and cytokine production in splenocytes. Cell proliferation and cytokine production (tumor necrosis factor; TNF-${\alpha}$, interleukin (IL)-6, IL-$1{\beta}$, and IL-12) tested in BMDC were significantly increased by PCP treatment. Additionally, the cell surface markers (CD 80/86, MHC class I/II) were highly increased by PCP treatment. For cytokine production in splenocytes, PCP treatment significantly increased the production of Th 1 cytokines [IL-2 and interferon (IFN)-${\gamma}$], but not Th 2 cytokines (IL-4). Therefore, PCP can induce immune cell activation and is a potential candidate for the development of nutraceuticals to boost the immune system.

• Applied Chemistry for Engineering
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• v.7 no.4
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• pp.605-613
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• 1996

The permeation characteristics were investigated for pure carbon dioxide and methane through asymmetric cellulose acetate(CA) membrane, composite cellulose acetate membrane and asymmetric cellulose triacetate(CTA) membrane. In particular, the effect of operating pressure on the permeation performance was examined. And the permeation behavior for a mixture of carbon dioxide and methane ($CO_2/CH_4=57.6/42.4$) was also investigated and compared to the characteristics obtained from pure gases. The experiments were run at the range of partial pressure from 25 to 125 psig, and room temperature. The permeation behaviors of the CA composite and CTA membrane were similiar to those of the CA membrane. The permeation rates of pure carbon dioxide for CA, CA composite and CTA membrane were increased slightly with an increase in upstream partial pressure, while in the case of pure methane they were independent of upstream partial pressure. For a binary mixture of carbon dioxide and methane, abnormal permeation behaviors were observed due to the plasticization of carbon dioxide and the competition effect of each gas. The separation factor and permeation rate for CTA membrane were found to be higher than those for CA membrane, but the mechanical strength of CTA membrane was very poor. And the permeation rate for CA composite membrane was higher than that for CA membrane. Consequently, it can be said that the CA composite membrane is a strong candidate for the separation of $CH_4$ and $CO_2$.

• Korean Journal of Clinical Laboratory Science
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• v.50 no.2
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• pp.118-125
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• 2018

Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis (MTB), but the genes associated with the host immune system can be attributed to the development of TB. The ITGB2 gene encodes the integrin beta 2 chain CD18 protein and is present on chromosome 21. The integrin beta 2 chain is an integrin expressed in leukocytes and plays a very important role in leukocyte maturation and attachment. ITGB2 plays an important role in the phagocytosis of MTB and the aggregation of leukocytes in MTB infections. This study examined the genetic polymorphisms of the ITGB2 gene between the TB case and normal control using Korean genomic and epidemiologic data. As a result, a statistically significant correlation was confirmed in 10 SNPs. The most significant SNP was rs113421921 (OR=0.69, CI: 0.53~0.90, $P=5.8{\times}10^{-3}$). In addition, rs173098, one of the significant 10 SNPs, is possibly located in a binding motif with the transcription factor cofactor p300, and can affect ITGB2 gene expression. These findings suggest that the pathogenesis of TB may be influenced by a range of genetic factors related to the immune function of the host, e.g., the reactions associated with the recruitment and attachment of leukocytes. The results of this study could be used to predict the infection control for tuberculosis in a patient-tailored manner.

• Journal of Embryo Transfer
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• v.25 no.4
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• pp.221-227
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• 2010

Early cleavage is a reliable prognostic tool for successful embryo transfer in assisted reproduction because early cleaved embryo show better pregnancy rate after transfer. There for, preparation of good embryo recipient is important factor to optimize efficiency of pig cloning. The present study was performed to evaluate the effect of early cleavage on the in vivo development of cloned embryos and to analyze breed, parity and estrous synchrony to optimize recipient for pig cloning. In vitro matured porcine oocytes derived from local slaughterhouse and fibroblasts derived from miniature pig fetuses were used for somatic cell nuclear transfer (SCNT). Reconstructed embryos were transferred to recipient pigs on the same day of SCNT or after 1~2 days of in vitro culture for selecting early cleaved embryos. Breed, parity and date of standing estrous of recipients were recorded for analysis. After 25~35 days after embryo transfer pregnancy was diagnosed using ultrasonography, and pregnant recipients were monitored till delivery. Between purebred and crossbred, no significant difference was founded in both pregnancy and delivery rates. However, early cleaved embryos showed significantly higher pregnancy (46.2%) and delivery (12.8%) rates compared to non-selectively transferred group (24.8% and 4.5%, respectively). The results also showed that the recipients showing standing estrous on the same day of SCNT and less than 4 parities were most suitable for pig cloning.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2000.04a
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• pp.3-6
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• 2000

Antimicrobial resistance has been a well-recognized problem ever since the introduction of penicillin into clinical use. History of antimicrobial development can be categorized based on the major antibiotics that had been developed against emerging resistant $pathogens^1$. In the first period from 1940 to 1960, penicillin was a dominating antibiotic called as a "magic bullet", although S.aureus armed with penicillinase led antimicrobial era to the second period in 1960s and 1970s. The second stage was characterized by broad-spectrum penicillins and early generation cephalosporins. During this period, nosocomial infections due to gram-negative bacilli became more prevalent, while those caused by S.aureus declined. A variety of new antimicrobial agents with distinct mechanism of action including new generation cephalosporins, monobactams, carbapenems, ${\beta}$-lactamase inhibitors, and quinolones characterized the third period from 1980s to 1990s. However, extensive use of wide variety of antibiotics in the community and hospitals has fueled the crisis in emerging antimicrobial resistance. Newly appeared drug-resistant Streptococcus pneumoniae (DRSP), vancomycin-resistant enterococci (VRE), extended-spectrum ${\beta}$-lactamase-producing Klebsiella, and VRSA have posed a serious threat in many parts of the world. Given the recent epidemiology of antimicrobial resistance and its clinical impact, there is no greater challenge related to emerging infections than the emergence of antibiotic resistance. Problems of antimicrobial resistance can be amplified by the fact that resistant clones or genes can spread within or between the species as well as to geographically distant areas which leads to a global concern$^2$. Antimicrobial resistance is primarily generated and promoted by increased use of antimicrobial agents. Unfortunately, as many as 50 % of prescriptions for antibiotics are reported to be inappropriate$^3$. Injudicious use of antibiotics even for viral upper respiratory infections is a universal phenomenon in every part of the world. The use of large quantities of antibiotics in the animal health industry and farming is another major factor contributing to selection of antibiotic resistance. In addition to these background factors, the tremendous increase in the immunocompromised hosts, popular use of invasive medical interventions, and increase in travel and mixing of human populations are contributing to the resurgence and spread of antimicrobial resistance$^4$. Antimicrobial resistance has critical impact on modem medicine both in clinical and economic aspect. Patients with previously treatable infections may have fatal outcome due to therapeutic failure that is unusual event no more. The potential economic impact of antimicrobial resistance is actually uncountable. With the increase in the problems of resistant organisms in the 21st century, however, additional health care costs for this problem must be enormously increasing.