• Bulletin of the Korean Mathematical Society
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• v.35 no.4
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• pp.791-807
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• 1998

The purpose of this paper is to construct a ring with unity under the derived cup product on the cochain groups of the inverse system and an isomorphism which is useful as the computation of a derived group by deleting the suitable terms in the directed set D. Moreover we apply these results to the K-theory.

• 한국균학회소식:학술대회논문집
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• 2006.10a
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• pp.19-23
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• 2006

Methods of lichen-derived culture were spore- and thallus-derived cultures. Spore-derived culture was modified and thallus-derived culture was established for our two decades. We maintained about 500 lichen-derived cultures by using both methods. In recent several years, we have investigated to screen various pharmacological activities in lichen-derived cultures for the first time and found some activities in our cultures.

• Communications of the Korean Mathematical Society
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• v.33 no.1
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• pp.53-71
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• 2018

In this paper, we provide two different descriptions for a relative derived category with respect to a subcategory ${\mathcal{X}}$ of an abelian category ${\mathcal{A}}$. First, we construct an exact model structure on certain exact category which has as its homotopy category the relative derived category of ${\mathcal{A}}$. We also show that a relative derived category is equivalent to homotopy category of certain complexes. Moreover, we investigate the existence of certain recollements in such categories.

• Korean Journal of Animal Reproduction
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• v.18 no.1
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• pp.7-13
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• 1994

To verify in vivo viability of IVF-derived bovine embryos, morula and blastocysts that developed from in vitro matured and fertilized ova were transferred to the uteri of recipient cows and normal calves were produced. To produce IVF-derived bovine morula or blastocysts, ova matured and fertilized in vitro were cultured in culture medium for 7~8 days at 39$^{\circ}C$ under the humicified atmosphere of 5% CO2. Two different culture systems, a co-culture system with TCM-199 and bovine epithelial cells (BOEC) and CR1aa without somatic cell support, were compared. Cleavage rates to 2~8 cell stage and developmental rates of IVF-derived bovine embryos to blastocyst stage were not different between co-culture system (51.3 and 14.0%) and CR1aa medium (60.4 and 22.1%), respectively. Embryos were classified into three grades by embryo quality and then one or two embryos in higher quality(A and B grades) were transferred to the uterus of recipients. In this study Korean Native calf was first born after transfer of IVF-derived embryos. Total four live calves were normally developed to term from IVF-derived bovine blastocysts and one female fetus was still-born approximatedly 8 months of gestation, but there was no pregnancy after transfer of morula. Therefore, normal calves could be produced after transfer of IVF-derived bovine embryos cultured in CR1aa medium without somatic cell support. In addition, our results suggest that in transfer of IVF-derived bovine embryos blastocyst stage is better than morula.

• Archives of Plastic Surgery
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• v.35 no.6
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• pp.653-658
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• 2008

Purpose: Skin and soft tissue defect is one of the major challenges faced by plastic surgeons. Adipose derived stromal cells, which can be harvested in large quantities with low morbidity, display multilineage mesodermal potential. Therefore, adipose derived stromal cells have been met with a great deal of excitement by the field of tissue engineering. Recently, Adipose derived stromal cells have been isolated and cultured to use soft tissue restoration. In order to apply cultured cells for clinical purpose, however, FDA approved facilities and techniques are required, which may be difficult for a clinician who cultures cells in a laboratory dedicated to research to utilize this treatment for patients. In addition, long culture period is needed. Fortunately, adipose derived stromal cells are easy to obtain in large quantities without cell culture. The purpose of this study is to present a possibility of using uncultured adipose derived stromal cells for wound coverage. Methods: Seven patients who needed skin and soft tissue restoration were included. Five patients had diabetic foot ulcers, 1 patient got thumb amputation, and 1 patient had tissue defect caused by resection of squamous cell carcinoma. The patients' abdominal adipose tissues were obtained by liposuction. The samples were digested with type I collagenase and centrifuged to obtain adipose derived stromal cells. The isolated adipose derived stromal cells were applied over the wounds immediately after the wound debridement. Fibrin was used as adipose derived stromal cells carrier. Occlusive dressing was applied with films and foams and the wounds were kept moist until complete healing. Results: One hundred to one hundred sixty thousand adipose derived stromal cells were isolated per ml aspirated adipose tissue. All patients' wounds were successfully covered with the grafted adipose derived stromal cells in a 17 to 27 day period. No adverse events related to this treatment occurred. Conclusion: The use of uncultured adipose derived stromal cells was found to be safe and effective treatment for wound coverage without donor site morbidity.

• Journal of Embryo Transfer
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• v.10 no.1
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• pp.83-90
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• 1995

Production of calves after transfer of nuclear transplant embryos is the latest technology to be applied in commercial livestock breeding. The objective of this study was to establish an efficient procedure to produce offsprings from nuclear transplant embryos. The fusion rates (72.7% vs. 80.8%), cleavage rates (62.5% vs. 71.4%) and rates of development in vitro (12.0% vs. 15.2%) of nuclear transplant embryos were not significantly different between 30 and 40h maturation age of cytoplast. The in vivo and in vitro-derived embryos as nuclei donor were used in this system of bovine nuclear transplantation. Fusion rates of nuclear transplant embryos were not significantly different between in vivo and in vitro-derived embryos (73.0 and 79.2%, respectively). The percentage of embryos reaching the morulae or blastocysts were 21.8% for in vivo-derived embryos and 11.9% for in vitro-derived embryos (p<0.01). Pregnancy rates after embryo transfer of nuclear transplant embryos were not significantly different between in vivo and in vitro-derived embryos (45.9 and 40.5%, respectively). However, calving rates after embryo transfer of nuclear transplant embryos were significantly higher in the in vivo-derived embryos than in vitro (p<0.01). Further research for age of cytoplast and use of in vitro-derived embryos as nuclei donor is required in this system. In conclusion, these results clearly show that the use of in vitro-derived oocytes as recipient cytoplast can improve the nuclear transplant system for genetic progress in cattle.

• Journal of Dairy Science and Biotechnology
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• v.21 no.2
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• pp.105-113
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• 2003

This study was carried out to investigate the addition of Pueraria derived isoflavone into milk by means of microencapsulation technique. The yield microencapsulation sensory attributes, and capsule stability of Pueraria derived isoflavone microcapsules in milk were measured during 12 days. Coating materials used was polyglycerol monostearate(PGMS. The encapsulation yield of Pueraria derived isoflavone was 72.5% with PGMS when the ratio of coating material to core material was 15:1. The rate of pueraria derived isoflavone release was 15, 20, and 25% when stored at 4, 20, and $30^{circ}C$ for 12 days in milk respectively. In sensory evaluation, beany flavor and color of microcapsuled Pueraria derived isoflavone added milk were significantly different from control and uncapsuled Pueraria derived isoflavone added milk, however, bitterness was not significantly different. In vitro study, microcapsules of pueraria derived isoflavone in simulated gastric fluid with the range of 3 to 6 pHs were released 3.0${\sim}$15.0%, however, the capsules in simulated intestinal fluid with pH 7 were released 95.7% for 40 min incubation time. In conclusion, this study provided that PGMS as coating materials was suitable for the microencapsulation of Pueraria derived isoflavone, and the capsule containing milk was not affected with sensory attribute.

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2756-2760
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• 2011

To develop more advanced binaphthol derived CSPs, two new 1,1-bi-2-naphthol derived chiral stationary phases (CSPs) (CSP 1 and CSP 2) were prepared by connecting with silica gel at a hydroxy (OH) group of binaphthol. Previously reported two 1,1'-binaphthyl-2,2'-diamine derived CSPs (CSP 3 and CSP 4) were also prepared to compare the role of their functional groups (-OH and -$NH_2$) with CSP 1 and CSP 2. Enantioseparation of randomly selected, 11 chiral compounds on these four CSPs was performed and the results compared to each other. 3,5-Dinitrobenzoyl (3,5-DNB) derivatives of each CSP showed better results than the others and binaphthyldiamine derived CSP showed slightly better than binaphthol derived one.

• Archives of Craniofacial Surgery
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• v.19 no.1
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• pp.20-34
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• 2018

Background: Polydeoxyribonucleotide (PDRN) influencing cellular growth and differentiation is recognized to promote wound healing by stimulating tissue repair. Although PDRN can be extracted from human placentas, PDRN medications have recently been extracted from the semen of trout (Oncorhynchus mykiss) and salmon (Oncorhynchus keta). The present study was designed to evaluate the wound healing effects of O. keta-derived PDRN for injection (Rejuvenex) and PDRN cream (Rejuvenex Cream) in comparison with those of O. mykiss-derived PDRN injection (Placentex). Methods: Full-thickness skin defects were made on the back of mice (n=60). The mice were divided into the following four groups according to the dressing used for the wounds: O. mykiss-derived PDRN injection group, O. keta-derived PDRN injection group, O. ketaderived PDRN cream group, and normal saline soaked dressing group (control group). We analyzed the gross findings, wound sizes, histological findings, immunohistochemistry and enzyme-linked immunosorbent assays for the groups immediately after the treatment, and again after 4, 7, and 10 days of treatment. Results: The wound healing effects were the greatest in the O. keta-derived PDRN injection and O. mykiss-derived PDRN injection groups, which showed similar scores, followed by the O. keta-derived cream and normal saline soaked dressing groups. Conclusion: The injection of PDRN extracted from O. keta was found to be as effective at healing full-thickness skin defects as the O. mykiss-derived PDRN injection, which is currently used in the clinic. Moreover, the O. keta-derived PDRN injection was also found to reduce the time required for wound healing.

• Journal of the Korean Society of Tobacco Science
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• v.10 no.1
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• pp.21-26
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• 1988

Ten anther-derived doubled haploid (ADH) and 10 maternally-derived doubled haploid fines (MDH) from NC 2326 were evaluated in the field to compare their performance. Both anther-derived doubled haploid and maternally-derived doubled haploid lines were agronomically inferior to selfed parental variety for many parameters, but the degree of inferiority of the MDH lines were not significantly different from the selfed parental variety for any character investigated. The inferiority of the ADH lines were, however, significantly different from the selfed parental variety for yield, leaf length and width , and days to flower.